Answer:
8
Step-by-step explanation:
f(n)= 6-2n
f(-1) = 6- 2(-1)
= 6+2
=8
Solve the equation.
8 -0.8k = 8
k = ?
(Simplify your answer.)
K = 0
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Find the unit rate.
1/3 kilometer in 1/3hour
Answer:
1 kilometer in 1 hour
Step-by-step explanation:
unit rate is km(kilometer) per hour(hr)
1/3 km = 1/3 hr
multiply both sides by 3
1 km in 1 hour
For what values are 2x^2=10x
[tex]\\ \sf\longmapsto 2x^2=10x[/tex]
Take to to right[tex]\\ \sf\longmapsto x^2=\dfrac{10x}{2}[/tex]
[tex]\\ \sf\longmapsto x^2=5x[/tex]
Cancel a x from both sides[tex]\\ \sf\longmapsto x=5[/tex]
✨Plz help me with my Homework!✨
This is “Finding unit rate”
Plz!
If (5x+3):(7x+3)=3:4, find the value of x.
[tex]\\ \sf\longmapsto \dfrac{5x+3}{7x+3}=\dfrac{3}{4}[/tex]
[tex]\\ \sf\longmapsto 4(5x+3)=3(7x+3)[/tex]
[tex]\\ \sf\longmapsto 20x+12=21x+9[/tex]
[tex]\\ \sf\longmapsto 12-9=21x-20x[/tex]
[tex]\\ \sf\longmapsto x=3[/tex]
[tex]\large\rm \longrightarrow \: {\purple{ \frac{(5x + 3)}{(7x + 3)} \: = \: \frac{3}{4} }} \\ [/tex]
⇛ Now , Cross Multiplying
[tex]\large\rm \longrightarrow \: {\blue{ 4 \: (5x + 3) \: = \: 3 \: (7x + 3)}}[/tex]
[tex]\large\rm \longrightarrow \: {\red{ 20x \: + \: 3 \: = \: 21 \: + \: 3}}[/tex]
[tex]\large\rm \longrightarrow \: {\orange{ 12 \: - \: 9 \: = \: 21x \: - \: 20x }}[/tex]
[tex]\large\rm \longrightarrow \:{\green{ 3 \: = \: x}}[/tex]
⇛ Hence , the value of x is 3
a² +6²
a-b
if a = 3 and b = 4
Evaluate each expression using the variable replacements.
Answer:
-45Step-by-step explanation:
let a= 3 and b= 4a² + 6² / a - b= 3² + 6² / 3 - 4= 9 + 36 / -1= 45 / -1= -45[tex]\tt{ \green{P} \orange{s} \red{y} \blue{x} \pink{c} \purple{h} \green{i} e}[/tex]
If triangle ABC has the following measurements, what is the measure of angle B? a=5 b=7 c=10
Answer: about 40.54°
Step by step explanation:
7^2 = 5^2 + 10^2 - 2(5)(10)cos(B)
cos(B) = (7^2 - 5^2 - 10^2) / (-2(5)(10) )
B = cos-1 [ (7^2 - 5^2 - 10^2) / (-2(5)(10) ] = cos-1 (.76) = about 40.54°
In a 4 day period, a delivery person delivered the following number of
packages per day: 1150, 1200, 1900 and 1350. The average number of
packages he delivered per day was _?_
Answer: 1400 packages
Step-by-step explanation:
1150+1200+1900+1350 divided by the 4 day interval means and average of:
1400 packages per day
For the function F defined by F(x) = x^2 – 2x + 4, find F(| – 4|).
| - 4 | = 4
Thus :
f ( | - 4 | ) = f ( 4 )
f ( 4 ) = ( 4 )^2 - 2(4) + 4
f ( 4 ) = 16 - 8 + 4
f ( 4 ) = 16 + 4 - 8
f ( 4 ) = 20 - 8
f ( 4 ) = 12
The area of rectangle is 36 cm2 and breadth is one fourth of the length.Find length and breadth of rectangle.
We know
[tex]\boxed{\sf Area=Length\times Breadth}[/tex]
[tex]\\ \sf\longmapsto x(4x)=36[/tex]
[tex]\\ \sf\longmapsto 4x^2=36[/tex]
[tex]\\ \sf\longmapsto x^2=\dfrac{36}{4}[/tex]
[tex]\\ \sf\longmapsto x^2=9[/tex]
[tex]\\ \sf\longmapsto x=\sqrt{9}[/tex]
[tex]\\ \sf\longmapsto x=3[/tex]
Breadth=3mLength=4(3)=12mA.Yes, since the slopes are the same and the y-intercepts are the same.
B.No, since the y-intercepts are different.
C.Yes, since the slopes are the same and the y-intercepts are different.
D.No, since the slopes are different.
Answer:
C
Step-by-step explanation:
one line is
y = 3x/7 + 11
its slope is 3/7
the y-intercept is, of course, when x=0. there y=11
the other is
-3x + 7y = 13
7y = 3x + 13
y = 3x/7 + 13/7
its slope is 3/7 (the same as the other line)
the y-intercept (x=0) is y = 13/7 (different to the other line)
Answer:
C. Yes, since the slopes are the same and the y-intercepts are different.
Step-by-step explanation:
[tex]y=\frac{3}{7} x+11[/tex] and [tex]-3x+7y=13[/tex]
→ Rearrange the second equation to make y the subject
7y = 3x + 13
→ Divide everything by 7
[tex]y=\frac{3}{7} x+\frac{13}{7}[/tex]
If a plane can climb at 2,400 feet per minute, how many minutes are needed to climb to 60,000 feet?
If a plane can climb at 2,400 feet per minute, how many minutes are needed to climb to 60,000 feet?
Answer:
25 is the amount needed to climb to 60,000 feet
Help!! Please I’m stuck give [10pts]
Answer:
x = 18
Step-by-step explanation:
To solve this problem, we can use the exterior angle theorem, which means the measure of an exterior angle is the sum of its remote interior angles. In this case, this would mean:
x + 72 = 5x
Since this gives us an equation, we can just solve for x:
x + 72 = 5x
72 = 4x
x = 18
Solve for s
1/3 s = 7
Answer:
21
[tex] \frac{1}{3} s = 7 \\ s = 7 \times 3 \\ s = 21[/tex]
The decimal for an irrational number never terminates or repeats. The
rational and irrational numbers together form the set of real numbers.
If false, explair:
Answer:
Step-by-step explanation:
No that is true. I can't make anything more out of it.
Adrian hopes that his new training methods have improved his batting average. Before starting his new regimen, he was batting 0.250 in a random sample of 56 at bats. For a random sample of 25 at bats since changing his training techniques, his batting average is 0.440. Determine if there is sufficient evidence to say that his batting average has improved at the 0.02 level of significance. Let the results before starting the new regimen be Population 1 and let the results after the training be Population 2. Step 2 of 3 : Compute the value of the test statistic. Round your answer to two decimal places.
According to the manufacturer's claim, we build an hypothesis test, find the test statistic and the p-value relative to this test statistic, we have that:
The value of the test statistic is z = 1.65.The p-value of the test is of 0.0495 > 0.02, which means that there is not sufficient evidence to say that his batting average has improved at the 0.02 level of significance.As the test involves a comparison of samples, it involves subtraction of normal variables, and for this, we need to understand the central limit theorem and subtraction of normal variables.
Central Limit Theorem
The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
For a proportion p in a sample of size n, the sampling distribution of the sample proportion will be approximately normal with mean [tex]\mu = p[/tex] and standard deviation [tex]s = \sqrt{\frac{p(1-p)}{n}}[/tex]
Subtraction between normal variables:
When two normal variables are subtracted, the mean is the difference of the means, while the standard deviation is the square root of the sum of the variances.
Before:
Average of 0.250 in 56 at bats, so:
[tex]p_B = 0.25[/tex]
[tex]s_B = \sqrt{\frac{0.25*0.75}{56}} = 0.0579[/tex]
After:
Average of 0.44 in 25 at bats, so:
[tex]p_A = 0.44[/tex]
[tex]s_A = \sqrt{\frac{0.44*0.56}{25}} = 0.0993[/tex]
Test if there was improvement:
At the null hypothesis, we test if there was no improvement, that is, the subtraction of the proportions is 0:
[tex]H_0: p_A - p_B = 0[/tex]
At the alternative hypothesis, we test if there was improvement, that is, the subtraction of the proportions is positive, so:
[tex]H_1: p_A - p_B > 0[/tex]
The test statistic is:
[tex]z = \frac{X - \mu}{s}[/tex]
In which X is the sample mean, [tex]\mu[/tex] is the value tested at the null hypothesis, and s is the standard error.
0 is tested at the null hypothesis:
This means that [tex]\mu = 0[/tex]
From the samples:
[tex]X = p_B - p_A = 0.44 - 0.25 = 0.19[/tex]
[tex]s = \sqrt{s_A^2 + s_B^2} = \sqrt{0.0579^2 + 0.0993^2} = 0.1149[/tex]
Value of the test statistic:
[tex]z = \frac{X - \mu}{s}[/tex]
[tex]z = \frac{0.19 - 0}{0.1149}[/tex]
[tex]z = 1.65[/tex]
P-value of the test and decision:
The p-value of the test is the probability of finding a difference of at least 0.19, which is 1 subtracted by the p-value of z = 1.65.
Looking at the z-table, z = 1.65 has a p-value of 0.9505.
1 - 0.9505 = 0.0495.
The p-value of the test is of 0.0495 > 0.02, which means that there is not sufficient evidence to say that his batting average has improved at the 0.02 level of significance.
A similar question is found at https://brainly.com/question/23827843
Find the gradient of the straight line joining the two points. (1,7) and (-1,-7)
Points: (-1,-7), (1,7)
Formula (y=mx+b):
y = 7x
Slope m: 7
Y-intercept b: 0
Parallel lines: 7x + any number
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The table below shows the number of pets kept by the students in a class.
-----------------------------------------------------------
No. of pets | No. of students
-----------------------------------------------------------
0 | 9
1 | k
2 | 2
3 | 1
4 | 2
-----------------------------------------------------------
If the median number of pets is 1, what is the smallest value of k ?
Answer:
The answer for this question is 5
7x to the power of 2 is a what is it
a) monomial
b) binomial
c) Trinomial
Explain why this quadrilateral is not a parallelogram.
Answer:
A parallelogram has two sets of parallel sides. This quadrilateral only has on set of parallel sides, so therefore it cannot be a parallelogram.
This graph represents which expression?
Answer:
x >7
Step-by-step explanation:
There is an open circle at 7, which means it cannot equal 7. The line goes to the right
x >7
What is the remainder when () = 3 − 11 − 10 is divided by x+3
Answer:
-18/x+3
Step-by-step explanation:
look at the image below
Answer:
201.1 km²
Step-by-step explanation:
Surface area of the figure,
4πr²
= 4×π×4²
= 64π
= 201.1 km² (rounded to the nearest tenth)
A letter is chosen from the word 'brilliant'. Determine the probability that it will be: Give your answers in their lowest terms.
Answer:
Step-by-step explanation:
brilliant has 9 letters
brilliant has 1 B (1/9)
brilliant has 1 R (1/9)
brilliant has 2 I's (2/9)
brilliant has 2 L's (2/9)
brilliant has 1 A (1/9)
brilliant has 1 N (1/9)
brilliant has 1 T (1/9)
How to solve using quadratic equations 4x^2+7x-20=0
Answer:
Step-by-step explanation:
Y = Ax2 Bx C
Enter coefficients here >>> 4 7 -20
Standard Form: y = 4x²+7x-20
1.75 0.875 0.765625 3.0625 -23.0625
Grouped Form: No valid Grouping
Graphing Form: y = 4(x+0.88)²-23.06
Factored Form: PRIME
Solution/X-Intercepts: -3.28 AND 1.53
Discriminate =369 is positive, two real solutions
VERTEX: (-0.88,-23.06) Directrix: Y=-23.13
Given f(x)=x^2 + x - 2, find the roots of g(x)=3f (-2x). Hint: Use the mapping rule.
[tex]f(x) = {x}^{2} + x - 2 \\ f( - 2x) = ( - 2x) ^{2} + ( - 2x) - 2 \\ = 4 {x}^{2} - 2x - 2 \\ \\ g(x) = 3f( - 2x) \\ g(x) = 3(4 {x}^{2} - 2x - 2) \\ = 12 {x}^{2} - 6x - 6 \\ = 6(2x + 1)(x - 1) \\ \\ g(x) = \sqrt{3f( - 2x)} \\ = \sqrt{3(4 {x}^{2} - 2x - 2)} \\ = \sqrt{12 {x}^{2} - 6x - 6} \\ = \sqrt{6(2x + 1)(x - 1)} \\ x = - \frac{1}{2} ,1[/tex]
From what I understood from the question I answered, I'm not sure about it , I hope this helps you ^_^
The sum of the ages of two Brothers is 43 years old and one of them is 15 years older than the other
Answer:
Age of younger brother is 14 years..
And age if elder brother is 29 years.
Step-by-step explanation:
Let us denote 'x' as the age of smaller brother,
then, the age of younger brother will be x+15 years.
Equation formed:-
x+x+15 =43
2x+15 = 43
2x = 43-15
2x = 28
X = 28/2
X = 14
Age of younger brother is 14 years.
Age of elder brother = x + 15
Age of elder brother 14 + 15 = 29 years.
giving brainliest! :)
Answer:
239=5
478=10
956=20
Step-by-step explanation:
Gianna's car can travel 478 mi with 10 gallons of gas
so, 47.8 mi with 1 gallon
by dividing 239 by 47.8 miles/gallon we get the answer 5 miles.
if we multiply 20 gallons by 47.8 mi/gallon #e get the answer 956 miles.
easy weasy
want to paint two walls in a room the height of the room is 2.5m and width of both walls is 4m calculate the area that needs to paint.
Answer:
As the room is in rectangular shape so
Length=2.5m
Breadth=4m
Area of wall=l×b
=2.5×4
=10m²
Thus, it is the area of 1 wall
Therefore area of 2 walls = area of 1 wall×2
=10×2
=20m²
Step-by-step explanation:
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Installation of certain hardware takes a random amount of time. The installation times form a normally distributed distribution with a standard deviation 5 minutes and a mean of 45 minutes. A computer technician installs the hardware on 31 different computers. You are interested to find the probability that the mean installation time for the 31 computers is less than 43 minutes.
Select the most appropriate item that pertains to the problem.
a. z=-0.4
b. none of these
c. z=-2.23
d. z=2.23
And,
What is the probability that the mean installation time for 31 computers is less than 43 minutes?
a. 0.400
b. 0.345
c. none of these
d. 0.0129
e. 0.987
The most appropriate values are:
z = - 2.23
The corresponding probability is : 0.01297
Mean, μ = 45
Standard deviation, σ = 5
Sample size, n = 31
The standard score, Z ; Since distribution is normal is obtained thus;
Z= (x - μ) ÷ (σ/√n)
For, x = 43
Z = (43 - 45) ÷ (5/√31)
Z = - 2.227
The probability :
Using the standard normal distribution table:
P(Z < - 2.227)
P = 0.01297
Hence, Z = - 2.23
P(x ≤ 43) = 0.0129
Learn more on Z probability :
https://brainly.com/question/4555552
