Find the sum of the first 40 terms of an arithmetic series whose first term is 7 and 40th term is 115. Type answer as an integer (no decimals)
arithmetic sum formula:
Sn = (a1 +
+ an)
geometric sum formula:
az (1 - p)
S =
1-r
Answer:

Answer:

7

Step-by-step explanation:

[tex]s = {a}^{2} \: thus \: a = \sqrt{s } = \sqrt{49} = 7[/tex]

Step-by-step explanation:

g(5)=2(5)-5=5

h(2)=4(2)+5=13

g(5)+h(2)=5+13=18

Answer:

94 cm.

Step-by-step explanation:

Perimeter = 25 + 2(10) + + 2(12) + 25

= 50 + 20 + 24

= 94 cm.

Answer:

4 :45 pm

Step-by-step explanation:

2 : 20 + 17 minutes = 2:37

2:37 + 1hr 1 minute  = 3 : 38

3 : 38 + 1 hr 7 = 4 :45 pm

Answer:

[tex]\frac{1}{x^{5} }[/tex]

Step-by-step explanation:

x^-12/ x^-7

= x^(-12-(-7))

= x^-5

= 1/x^5

Answer:

The answer is "[tex]f(x) = 3(1.05)x + 2[/tex]".

Step-by-step explanation:

She starts off with 3 hours with pop music.

Next month, she will have 3 hours she has had and + 3*0.05.

3hrs + 3*0.05hrs = 3*1.05 hrs

We add 2 hours of classical music to the 3 * 1.05 hours to achieve 3 * (1.05) hours + 2 hours of classical music.

Answer: f(x):2(0.05)^x+3

Answer:

y=3x+9......(i)

y=-4x-12...(ii)

these are the equation

Answer:

x = 94

Step-by-step explanation:

The sum of the 4 angles in a quadrilateral = 360°

Sum the 4 angles and equate to 360

x + x + 2x - 75 + x - 35 = 360

5x - 110 = 360 ( add 110 to both sides )

5x = 470 ( divide both sides by 5 )

x = 94

Answer:

option D is false it's not parallelogram

Answer:

its c

Step-by-step explanation:

i did it on ed

Answer:

Heres the answer!

Step-by-step explanation:

Answer:

Cost of 1 goggles = $20

Cost of 1 mask = 15

Step-by-step explanation:

Given:

Cost of 2 goggles and 1 mask = $55

Cost of 1 goggles and 2 mask = $50

Find:

Cost of each goggles and mask

Computation:

Assume;

Cost of 1 goggles = a

Cost of 1 mask = b

So,

2a + b = 55.....EQ1

a + 2b = 50.......EQ2

EQ1 x 2

4a + 2b = 110 ......EQ3

EQ3 - EQ2

3a = 60

a = 20

Cost of 1 goggles = $20

a + 2a = 50

20 + 2b = 50

2b = 30

b = 15

Cost of 1 mask = 15

.

Answer:

10t + D = 40

Step-by-step explanation:

y = mx + b is the equation of a line in slope intercept form. We'll be using this equation since the slope, or distance traveled, is steady (linear). In this case, the slope is 10 since Sarah's pace is 10 km/hr. m is the slope, so m = 10.

y = 10x + b. However, she needs to run 40 km. So we're going to substitute 40 in for y.

40 = 10x + b. Now, we need to use t instead of x since that's what's been asked of us. (The slope represents the distance traveled over time, so t fits.)

10t + b = 40

b needs to become D, the distance in kilometers.

So now we have 10t + D = 40

Answer:

D(t)= 40-10t

Step-by-step explanation:

#KmNn

Answer:

3x + 11

Step-by-step explanation:

1) Remove Parentheses:

x + 4 + 2x + 7

2) Combine Like Terms:

(2x + x) and (4 + 7)

3) Simplify:

3x + 11

Hope this helps, good luck! Have a good day. :)

Step-by-step explanation:

To evaluate such, the following formula is required:

Distance Formula: d(P, Q) = √ (x2 − x1)^2 + (y2 − y1)^2

Denote the following points as the following,

(4, -7). (1, -7)

X1 Y1. X2. Y2

D(P, Q) = √(1 - 4)^2 + (-7 + 7)^2. <== Since there is a double negative, such will be considered addition.

√(-3)^2 + (0)^2

√9 = 3

Thus, the agglomerate distance of such points on the Cartesian plane is disclosed as 3 units.

Answer:

5.30

Step-by-step explanation:

Total cost = flat fee + cost per mile * number of miles

              c(m)  = 3.50 + .60m

Let m=3

c(3)  = 3.50 + .60(3)

    = 3.50 + 1.80

    =5.30

Answer:

B: $5.30

Step-by-step explanation:

Each mile is $0.6, to get the result for 3 miles we would need to multiply $0.6 by 3. $0.60 * 3 = $1.8. Finally we would need to add the 3.50 to $1.8 resulting in $5.30

The shape is an irregular pentagon

Answer:

y-intercept = 3

Step-by-step explanation:

value that's on the y - axis

Look in the images it is solved.

Out of 120 students in exam, 2/3 of them passed. How many students passed?

now,

no of students passed = 2/3×120

= 0.66×120

=80...

therefore 80 students were passed....

Answer:

80

Step-by-step explanation:

Answer:

im not sure but i got 30.1

Step-by-step explanation:

[tex] \cos(x) = \frac{45}{52} \\ x = 30.1[/tex]

Part (i)

We have 60 students total, and 5 didn't like any of the two subjects, so that must mean 60-5 = 55 students liked at least one subject.

=========================================================

Part (ii)

We have 15 who like math only, 20 who like science only, and 55 who like either (or both). Let x be the number of people who like both classes.

We can then say

15+20+x = 55

x+35 = 55

x = 55-35

x = 20

This means 20 people liked both subjects

=========================================================

Part (iii)

There are 15 people who like math only, and 20 who like both. Therefore, there are 15+20 = 35 people who like math (and some of these people also like science)

=========================================================

Part (iv)

We'll follow the same idea as the previous part. There are 20 people who like science only and 20 who like both subjects. That yields 40 people total who like science (and some of these people also like math).

=========================================================

Part (v)

We'll draw a rectangle to represent the entire group of 60 students. This is considered the universal set. Inside the rectangle will be two overlapping circles to represent math (M) and science (S).

We'll have 15 go in circle M, but outside circle S to represent the 15 people who like math only. Then we have 20 go in circle S but outside circle M to show the 20 people who like science only. We have another copy of 20 go in the overlapped region between the circles. This is the 20 people who like both classes. And finally, we have 5 go outside both circles, but inside the rectangle. These are the 5 people who don't like either subject.

Note how all of the values in the diagram add up to 60

15+20+20+5 = 60

This helps confirm we have the correct values.

Answer:

  (a)  no solution

Step-by-step explanation:

Writing the second equation in slope-intercept form, it becomes ...

  3x -y = 2 . . . . given

  y = 3x -2 . . . . add y-2 to both sides

The first equation is already in slope-intercept form:

  y = 3x +3 . . . . first equation

The coefficients of x in the two equations are both 3, so the lines they describe are parallel. They do not intersect, so there is no solution.

x= - 1/2,-1

or

x= - 0.5, -1

Answer:

x = -1/2  x=-1

Step-by-step explanation:

2x( x+1.5) = -1

Distribute

2x^2 + 3x = -1

Add 1 to each side

2x^2 +3x+1 = 0

Factor

(2x+1) (x+1) =0

Using the zero product property

2x+1 = 0   x+1=0

2x = -1    x=-1

x = -1/2  x=-1

Answer:

2x

Step-by-step explanation:

Just solve the function operation:

f/g=(2x/2x+1)/(1/2x+1) = 2x since (2x/1)/(2x+1/2x+1) simplifies to 2x/1 the answer is 2x

composite numbers less than 12={1,3,4,6,8,9,10}

Answer:

O I, II, and III only

Step-by-step explanation:

x-3 < 2

Add 3 to each side

x-3+3< 2+5

x<5

-3 is less than 5

0 is less than 5

2 is less than 5

5 is not less than 5

I , II , II are true

from 0 to 20

neither the seconds nor the height are likely to be negative.

Answer:

SinA= BC/AC=20/55

SinA=4/11

A=Sin^-1(4/11)

A=Sin^-1(0.36)

LA=21.1 ← ans

OAmalOHopeO

Recall the definition of absolute value:

• |x| = x if x ≥ 0

• |x| = -x if x < 0

So you need to consider 4 different cases (2 absolute value expressions with 2 possible cases each).

(i) Suppose 2x + 3 < 0 and x - 2 < 0. The first inequality says x < -3/2 and the second says x < 2, so ultimately x < -3/2. Then

|2x + 3| + |x - 2| = 6x

-(2x + 3) - (x - 2) = 6x

-2x - 3 - x + 2 = 6x

-3x - 1 = 6x

9x = -1

x = -1/9

But -1/9 is not smaller than -3/2, so this case provides no valid solution.

(ii) Suppose 2x + 3 ≥ 0 and x - 2 < 0. Then x ≥ -3/2 and x < 2, or -3/2 ≤ x < 2. Under this condition,

|2x + 3| + |x - 2| = 6x

(2x + 3) - (x - 2) = 6x

2x + 3 - x + 2 = 6x

x + 5 = 6x

5x = 5

x = 1

This solution is valid because it does fall in the interval -3/2 ≤ x < 2.

(iii) Suppose 2x + 3 < 0 and x - 2 ≥ 0. Then x < -3/2 or x ≥ 2. So

|2x + 3| + |x - 2| = 6x

-(2x + 3) + (x - 2) = 6x

-2x - 3 + x - 2 = 6x

-x - 5 = 6x

7x = -5

x = -5/7

This isn't a valid solution, because neither -5/7 < -3/2 nor -5/7 ≥ 2 are true.

(iv) Suppose 2x + 3 ≥ 0 and x - 2 ≥ 0. Then x ≥ -3/2 and x ≥ 2, or simply x ≥ 2.

|2x + 3| + |x - 2| = 6x

(2x + 3) + (x - 2) = 6x

2x + 3 + x - 2 = 6x

3x + 1 = 6x

3x = 1

x = 1/3

This is yet another invalid solution since 1/3 is smaller than 2.

So there is one solution at x = 1.