What should you multiply the top equation by so that yis eliminated when the equations are added? | 3x – y = -2 15x + 2y = 15 A. 4 B. -2 C. 2 D. -1

Answers

Answer 1

Answer:

c. 2

Step-by-step explanation:

 2 (3x – y = -2)               6x - 2y = -4

6x - 2y = -4


Related Questions

Solve the formula for the indicated variable.
1
A=-bh, for h
2
- BA

Answers

Answer:

perdón yo no hablo inglés

solve the equation 7*2=?​

Answers

Answer:

7*2=14

Step-by-step explanation:

7*2=14 because is multiplication

Answer:

14 because it is multiplication

Using the Factor Theorem, which of the polynomial functions has the zeros 2, radical 3 , and negative radical 3 ? f (x) = x3 – 2x2 – 3x + 6 f (x)= x3 – 2x2 + 3x + 6 f (x) = x3 + 2x2 – 3x + 6 f (x) = x3 + 2x2 – 3x – 6

Answers

Answer:

A

[tex]f(x) = x^3 - 2x^2 -3x + 6[/tex]

Step-by-step explanation:

According to the Factor Theorem, if (x - k) is a factor of a polynomial P(x), then P(k) must equal zero.

We are given that a polynomial function has the zeros 2, √3, and -√3. So, we can let k = 2, √3, -√3.

So, according to the Factor Theorem, P(2), P(√3) and P(-√3) must equal 0.

Testing each choice, we can see that only A is true:

[tex]\displaystyle f(x) = x^3 - 2x^2 - 3x + 6[/tex]

Testing all three values yields that:

[tex]\displaystyle \begin{aligned} f(2) &= (2)^3 - 2(2)^2 -3(2) + 6 \\ &= (8) - (8) -(6) + (6) \\ &= 0\stackrel{\checkmark}{=}0 \\ \displaystyle f(\sqrt{3}) &= (\sqrt{3})^3 - 2(\sqrt{3})^2 - 3(\sqrt{3}) + 6 \\ &=(3\sqrt{3}) -(6)-(3\sqrt{3}) + 6 \\ &= 0\stackrel{\checkmark}{=}0 \\ f(-\sqrt{3}) &= (-\sqrt{3})^3 - 2(-\sqrt{3})^2 - 3(-\sqrt{3}) + 6 \\ &=(-3\sqrt{3}) -(6)+(3\sqrt{3}) + 6 \\ &= 0\stackrel{\checkmark}{=}0 \end{aligned}[/tex]

Hence, our answer is A.

Write each rate as a fraction in lowest terms
20 feet in 30 seconds

Answers

Answer:

[tex] = { \boxed{ \sf{ \frac{2}{3} }}} \: { \tt{feet/sec }}[/tex]

Answer:

2/3

Step-by-step explanation:

The basic formula is d = r * t. The units are important. Time is usually recorded as seconds. d can be feet or meters in standard form. The formula has to be rearranged to get r by itself.

r = d/ t

d = 20 feet

t = 30 seconds

r = 20 feet / 30 seconds

r = 20 ft/sec

Even though you are told not to enter the units, it is still important to recognize what they are.

The mean output of a certain type of amplifier is 335335 watts with a standard deviation of 1212 watts. If 7070 amplifiers are sampled, what is the probability that the mean of the sample would be greater than 338.4338.4 watts

Answers

Answer:

.3885 = 38.85%

Step-by-step explanation:

*Probability-Above 38.85%

Z1=0.28 Z2=-27.92

*x-1 338.4

 

*µ 335

*σ 12

please help! thanks!
find y.

Answers

Answer:

y = 4

Step-by-step explanation:

The ratio of the lengths of the sides of a 30-60-90 triangle is

1 : √3 : 2

The sides in this triangle are in the order:

y : 4√3 : x

y/1 = 4√3/√3

y = 4

Example 2.20
Solution
After 7% discount, Faizal get RM1,930 from a bank. He then promised to pay the bank RM2,000
after x days. Determine the value of x.
Kaspersk
Th​

Answers

The period of days (value of x) for which Faizal promised to pay the bank RM 2,000 after getting 7% discounted present value of RM 1,930 is 180 days.

The value of x is the period of days (number of days) that the loan from the bank will last before Faizal, who received RM 1,930 discounted at 7%, would repay the bank the principal and interest of RM 2,000.

This implies that Faizal is paying an interest of RM 70 (RM 2,000 - RM 1,930), since he borrowed RM 1,930 and will repay RM 2,000.

Data and Calculations:

Present value of loan received = RM 1,930

Discount rate per year = 7%

Future value of the loan to be repaid to the bank = RM 2,000

Interest expense for one year based on 7% = RM 140 (RM 2,000 x 7%)

Interest expense for 180 days or 6 months = RM 70 (RM 2,000 - RM 1,930) or (RM 2,000 x 7%) x 180/360

Interest expense that equals RM 70 will be half of a year or 180 days (RM 140 * 180/360)

Thus, the period of days (x) that will lapse for Faizal to repay the bank is 180 days or half of a year (6 months).

Learn more about time period of a loan here: https://brainly.com/question/19118285

√10 Multiple √15 is equal to

(a) 6√5

(b) √30

(c) √25






step by step








Solve :-​

dont answer stantham​

Answers

[tex]\\ \sf\longmapsto \sqrt{10}\times \sqrt{15}[/tex]

[tex]\\ \sf\longmapsto \sqrt{10\times 15}[/tex]

[tex]\\ \sf\longmapsto \sqrt{2\times 5\times 3\times 5}[/tex]

[tex]\\ \sf\longmapsto \sqrt{5\times 5\times 6}[/tex]

[tex]\\ \sf\longmapsto 5\sqrt{6}[/tex]

None of the above should be 4th option

Instructions: Find the missing side. Round your answer to the
nearest tenth

Answers

Answer:

49

Step-by-step explanation:

sin(theta) = P/H

sin(28)=23/x, x=23/sin(28)=49

Identify the triangle, ABC, which has a 72∘ angle and a 36∘ angle.

Answers

Answer:

isosceles acute

Step-by-step explanation:

sum of angles in a triangle = 180

to find third angle, subtract 72 & 36 from 180 and you get 72

72, 36, and 72 are all less than 90 so it will be an acute triangle

It will also be isosceles bc there are 2 angles of the same measure

simplify
7(a²)³ x 8a⁵ / 4a⁷ and explain

Answers

Answer: 14a^4

Step-by-step explanation:

.. Find the L.C.M. of (a - 5)(a – 4) and (a + 4)(a – 5)​

Answers

A-5 A-5 AND A-4 A-5

A-10 AND A-1

Hope it helps you

Evaluate 3x ^ 2 + 3x - 9 , when x = 2

A=-3
B=3
C=9
D=27

Answers

Answer:

C. 9

Step-by-step explanation:

Start plugging in the number 2

3(2)^2+3(2)-9

6^2+6-9

12+6-9

18-9

9

Which proportion would you use to solve the following problem? A map has a scale of 1 cm : 5 km. Determine how far apart two cities are if they are 8 cm apart on the map. A. B. C. D.

Answers

Answer:

40 km

Step-by-step explanation:

We can use a ratio to solve

1 cm       8 cm

-------- = ----------

5 km        x km

Using cross products

1 * x = 5 * 8

x = 40

40 km

[tex]\bf \large{\pink{ \implies}} \tt \: \frac{1 \: cm}{5 \: km} \: = \: \frac{8 \: cm}{x} \: \: \: \rm{\red{ (cross \: \: multiplying)}}[/tex]

[tex]\bf \large{\pink{ \implies}} \tt \:x \: = \: 40[/tex]

⇛ Distance is 40 km

What type of counting problem is this?

Johnny is a very picky eater, so he likes to use a lot of condiments. He has ketchup, salt, pepper, and shredded cheese at his disposal. His mother tells him he may only make two additions to his meal (i.e., he can add condiments only twice, regardless of whether or not he already used them). How many different ways can Johnny improve his meal?
A.Combination with repetition
B.Combination without repetition
C.Permutation with repetition
D.Permutation without repetition

Answers

Answer:

option A

Step-by-step explanation:

Permutation is An arrangement of objects in an ORDER

but combination is the opposite.

In this question, There is a combination! I hope this helped! have a great day!

-8=8(-3+a) plz help me and show work simply

Answers

Answer:

[tex] - 8 = 8( - 3 + a) \\ - 8 = - 24 + 8a \\ 8a = 16 \\ a = 2[/tex]

Answer:

2

Step-by-step explanation:

-8 = 8a - 24

16 = 8a

a =2

I hope this helps! :)

write down the length of the diameter of the circle​

Answers

Answer:

Diameter = 2 × Radius

Step-by-step explanation:

Answer:

Step-by-step explanation:

The diameter of a circle is the length of the line through the center and touching two points on its edge. In the figure above, drag the orange dots around and see that the diameter never changes. The diameter is also a chord.

40 points if answered

ZA and B are supplementary angles. If m A = (82 + 6)° and m
B = (72 +24), then find the measure of ZB.

Answers

Answer:

94

Step-by-step explanation:

Supplementary angles add to 180

8x+6  + 7x+24 = 180

Combine like terms

15x+30=180

Subtract 30 from each side

15x+30-30 = 180-30

15x= 150

Divide by 15

15x/15 = 150/15

x = 10

We want to find angle B

B = 7x+24 = 7*10+24 = 70+24 = 94

Answer:

Supplementary angles are angles that add up to 180 degrees (in other words, make up a straight line when you put them together).  

So we can write: (8x+6) + (7x+24) = 180

Combine like terms: 15x+30 = 180

Subtract: 15x = 150

Divide: x = 10

If x = 10, and the measure of angle B can be written as 7x+24, then the measure of angle b is 7(10)+24, or 94.

Let me know if this helps!

write all the prime numbers between 10 and 30.​

Answers

It's 11, 13, 17, 19, 23 and 29.

Solve the system of equations.
3x + 4y + 3z = 5
2x + 2y + 3z = 5
5x+ 6y+7z = 7
a. (x = 13, y=-6, z = -2)
b. (x = 15, y = -8, z = -4)
c. (x = 16, y = -9, z = -1)
d. (x = 14, y = -7, z = 3)

Answers

Answer:

x = 14

y = -7

z = -3

but this is none of the provided answer options !

Step-by-step explanation:

it's really easy by principle. it's just some work to do.

we try to find equations to express one variable in terms of the others.

but one thing there is : your teacher made a mistake.

the right solution is x = 14, y = -7, z = -3

your teacher made a typo at d.

but the right answer should be d.

just to give you an idea how this can be done (and also to prove that there is a mistake by the teacher):

we can directly try to transform one expression into one that describes x by y and z.

and then another to describe e.g. z by y. and then solve the third one just for y. and then we get the other 2 by these other expressions.

or we can e.g. add or subtract one equation to/from another. this is one of these cases, because we can find really simple expressions that way :

we do

5x + 6y + 7z = 7

- (3x + 4y + 3z = 5)

- (2x + 2y + 3z = 5)

---------------------------

0x + 0y + z = -3

=> z = -3

3x + 4y - 3×3 = 5

3x = -4y + 14

x = (-4y + 14)/3

2×(-4y + 14)/3 + 2y - 9 = 5

(-8y + 28)/3 + 2y = 14

-8y + 28 + 6y = 42

-2y = 14

y = -7

x = (-4×-7 + 14)/3 = (28+14)/3 = 42/3 = 14

The product of x and its opposite is always 1.
O True
O False

Answers

Answer:

False

Step-by-step explanation:

x

The opposite of x is -x

x* -x = -x^2

This is not always 1

Answer:

false

Step-by-step explanation:

x*-x= - x ² so its not always 1

so I just started using brainly sorry if its not appropriate

Which transformations are needed to change the parent sine function to y = one-fourth sine (4 (x + StartFraction pi Over 6 EndFraction))? vertical stretch of One-fourth, horizontal stretch to a period of 2p, phase shift of StartFraction pi Over 6 EndFraction units to the left vertical compression of One-fourth, horizontal compression to a period of StartFraction pi Over 2 EndFraction, phase shift of StartFraction pi Over 6 EndFraction units to the left vertical stretch of 4, horizontal stretch to a period of 8p, phase shift of StartFraction pi Over 6 EndFraction units to the right vertical compression of 4, horizontal compression to a period of StartFraction pi Over 4 EndFraction, phase shift of StartFraction pi Over 6 EndFraction units to the right

Answers

Answer: Option B is correct

Step-by-step explanation: edge 2021

Answer:

b

Step-by-step explanation:

Stuck on this problem

Answers

9514 1404 393

Answer:

  -8,257,536·u^5·v^10

Step-by-step explanation:

The expansion of (a +b)^n is ...

  (c0)a^nb^0 +(c1)a^(n-1)b^1 +(c2)a^(n-2)b^2 +... +(ck)a^(n-k)b^k +... +(cn)a^0b^n

Then the k-th term is (ck)a^(n-k)b^k, where k is counted from 0 to n.

The value of ck can be found using Pascal's triangle, or by the formula ...

  ck = n!/(k!(n-k)!) . . . . where x! is the factorial of x, the product of all positive integers less than or equal to x.

This expansion has 11 terms, so the middle one is the one for k=5. That term will be ...

  5th term = (10!/(5!(10-5)!)(2u)^(10-5)(-4v^2)^5

  = (252)(32u^5)(-1024v^10) = -8,257,536·u^5·v^10


A square and a rectangle have the same area. If the dimensions of the rectangle are 4 ft by 16 ft, how long is a side of the square?

Answers

Answer:

8

Step-by-step explanation:

4×16=64

[tex] \sqrt{64 } = 8[/tex]

Find the final amount in each of these retirement accounts, in which the rate
of return on the account and the regular contribution change over time,
(a) $400 per month invested at 4%, compounded monthly, for 10 years, then
$600 per month invested at 6%, compounded monthly, for 10 years
(b) $1,000 per quarter invested at 4.42%, compounded quarterly, for 10 years,
then $1,500 per quarter invested at 7.4%, compounded quarterly, for 15
years

Answers

Answer:

Compound Interest: The future value (FV) of an investment of present value (PV) dollars earning interest at an annual rate of r compounded m times per year for a period of t years is:

FV = PV(1 + r/m)mt

or

FV = PV(1 + i)n

where i = r/m is the interest per compounding period and n = mt is the number of compounding periods.

One may solve for the present value PV to obtain:

PV = FV/(1 + r/m)mt

Numerical Example: For 4-year investment of $20,000 earning 8.5% per year, with interest re-invested each month, the future value is

FV = PV(1 + r/m)mt = 20,000(1 + 0.085/12)(12)(4) = $28,065.30

Notice that the interest earned is $28,065.30 - $20,000 = $8,065.30 -- considerably more than the corresponding simple interest.

Effective Interest Rate: If money is invested at an annual rate r, compounded m times per year, the effective interest rate is:

reff = (1 + r/m)m - 1.

This is the interest rate that would give the same yield if compounded only once per year. In this context r is also called the nominal rate, and is often denoted as rnom.

Numerical Example: A CD paying 9.8% compounded monthly has a nominal rate of rnom = 0.098, and an effective rate of:

r eff =(1 + rnom /m)m = (1 + 0.098/12)12 - 1 = 0.1025.

Thus, we get an effective interest rate of 10.25%, since the compounding makes the CD paying 9.8% compounded monthly really pay 10.25% interest over the course of the year.

Mortgage Payments Components: Let where P = principal, r = interest rate per period, n = number of periods, k = number of payments, R = monthly payment, and D = debt balance after K payments, then

R = P × r / [1 - (1 + r)-n]

and

D = P × (1 + r)k - R × [(1 + r)k - 1)/r]

Accelerating Mortgage Payments Components: Suppose one decides to pay more than the monthly payment, the question is how many months will it take until the mortgage is paid off? The answer is, the rounded-up, where:

n = log[x / (x – P × r)] / log (1 + r)

where Log is the logarithm in any base, say 10, or e.

Future Value (FV) of an Annuity Components: Ler where R = payment, r = rate of interest, and n = number of payments, then

FV = [ R(1 + r)n - 1 ] / r

Future Value for an Increasing Annuity: It is an increasing annuity is an investment that is earning interest, and into which regular payments of a fixed amount are made. Suppose one makes a payment of R at the end of each compounding period into an investment with a present value of PV, paying interest at an annual rate of r compounded m times per year, then the future value after t years will be

FV = PV(1 + i)n + [ R ( (1 + i)n - 1 ) ] / i

where i = r/m is the interest paid each period and n = m × t is the total number of periods.

Numerical Example: You deposit $100 per month into an account that now contains $5,000 and earns 5% interest per year compounded monthly. After 10 years, the amount of money in the account is:

FV = PV(1 + i)n + [ R(1 + i)n - 1 ] / i =

5,000(1+0.05/12)120 + [100(1+0.05/12)120 - 1 ] / (0.05/12)

Step 1: Choose the price of the house. Then calculate 20% (which will be your down payment). Write down the price and 20% of the price.


Step 2: You don't have 20% now, so you will use an annuity to save up until you have the 20%. Choose a time in the future (2 years, 3 years, 4 years, 5, 10?) that you will purchase this house. Choose an APR that the bank will give you. Calculate how much you need to deposit every month in order to have the 20% down payment down the road. Write down the numbers of years, the interest rate, the formula with all the numbers plugged in, and the monthly deposits you will need to make.


Step 3: Now you take out a mortgage on the remaining 80%. Choose an APR that the bank will charge you (to be realistic, more than the APR in step 2) and the time you will take to pay off the loan. Write down the formula with all the numbers plugged in, and write down the minimum monthly payments.


Please show me proper work and a step by step explanation on how you got your answers. Anyone who attempts to answer just to steal points will be reported. Btw this is due midnight tonight so I could really use some help with this

Answers

9514 1404 393

Answer:

$250,000 house price. $50,000 down payment2 years, 3% from the bank, monthly: $2024.065% APR, 30 years, monthly: 1073.64

Step-by-step explanation:

1. House prices vary considerably. In January, 2021, the median US house price was about $269,000, growing at the rate of about 3.2% per year. For the purpose of this problem, we have chosen a slightly lower price of ...

   $250,000 . . . selected house price

20% of this price is ...

  0.20 × $250,000 = $50,000 . . . amount of down payment

__

2. House prices are growing faster than the interest rate we can get at the bank, so we want to minimize the amount of time we save for a down payment. At the same time, we recognize that saving this amount quickly will put a significant strain on the budget. We choose a period of 2 years, and assume a bank rate on savings of 3%. (US rates in mid-2021 average about 0.04%.) This annuity formula gives the future value of a series of payments:

  A = P((1+r/12)^(12t)-1)(12/r) . . . . monthly payment P at annual rate r for t years

Solving for P, we have ...

  P = A(r/12)/((1 +r/12)^(12t) -1)

Filling in the chosen numbers, we find we need to save ...

  P = $50,000(0.03/12)/(1 +0.03/12)^(12·2) -1) = $50,000(0.0025)/0.06175704

  P = $2024.06

$2024.06 needs to be deposited every month for 2 years at 3%.

__

3. The mortgage will be for ...

  $250,000 -50,000 = $200,000

We assume we can get an APR of 5% on a 30-year loan. (US rates in mid-2021 are around 3.2%.) The formula for the payment amount is ...

  A = P(r/12)/(1 -(1 +r/12)^(-12t)) . . . principal P at rate r for t years

Filling in the chosen numbers, we find the monthly payment to be ...

  A = $200,000(0.05/12)/(1 -(1 +0.05/12)^(-12·30))

  = $200,000(0.0041666667)/0.77617340 = $1073.64

The monthly mortgage payment will be $1073.64.

Find the least whole number that can replace
to make the statement true.
110< =47

Answers

Answer:

it is false

Step-by-step explanation:i cant explain but trust

a swift can fly at 160km/h. what is the speed in m/s? show clearly how you worked out your answer.

Answers

Answer:

[tex]\huge\boxed{\sf Speed = 44.44 \ m/s}[/tex]

Step-by-step explanation:

Speed = 160 km / hr

To convert km/hr to m/s, we multiply it by [tex]\sf \frac{10}{36}[/tex]

Hence,

[tex]\displaystyle Speed = 160 \times \frac{10}{36} \ m/s\\\\Speed = \frac{1600}{36} \ m/s\\\\Speed = 44.44 \ m/s\\\\\rule[225]{225}{2}[/tex]

Hope this helped!

~AH1807Peace!

The sum of 'n' terms of an arithmetic sequence is 4n2+3n. What is the first term, the common difference, and the sequence?

Answers

Answer:

Step-by-step explanation:

If the 2 is an exponent, it should be indicated with a circumflex:  4n^2+3n.

What is the first term?

a₁ = S₁ = 4·1² + 3·1 = 7

:::::

What is the common difference?

a₁ + a₂ = S₂ = 4·2² + 3·2 = 22

a₂ = 22-a₁ = 15

common difference d = a₂ - a₁ = 8

:::::

What is the arithmetic sequence?

The nth term is 7+(n-1)d = 7+(n-1)8 = 8n-1.

a₁ = 8·1-1 = 7

a₂ = 8·2-1 = 15

a₃ = 8·3-1 = 23

...

At what point on the curve x = 6t2 + 6, y = t3 − 2 does the tangent line have slope 1 /2 ?

Answers

Answer:

Hello,

P=(30,6)

Step-by-step explanation:

[tex]x=6t^2+6\\y=t^3-2\\\\\dfrac{dx}{dt}= 12t\\\dfrac{dy}{dt}= 3t^2\\\\\dfrac{dy}{dx} =\dfrac{\dfrac{dy}{dt} }{\dfrac{dx}{dt} } =\dfrac{3t^2}{12t} =\dfrac{t}{4} \\\\\dfrac{t}{4} =\dfrac{1}{2} \Longrightarrow t=2\\\\\\x=6t^2+6=6*2^2+6=30\\\\y=t^3-2=2^2-2=8-2=6\\\\\\Tangence\ point=(30,6)\\[/tex]

The point on the curve x = 6t² + 6, y = t³ - 2 where the tangent line have slope 1/2 is (30, 6).

How to depict the point on the curve?

From the information given, x = 6t² + 6, y = t³ - 2. We'll find the first order derivative of x and y which will be:

dx/dt = 12t

dy/dt = 3t²

Therefore, 3t²/12t = t/4, t = 2.

We'll put the value of t back into the equations.

x = 6t² + 6,

x = 6(2)² + 6

x = 24 + 6 = 30

y = t³ - 2.

y = (2)³ - 2

y = 8 - 2 = 6

In conclusion, the correct options is (30, 6).

Learn more about slope on:

https://brainly.com/question/3494733

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