Find the domain and range of the following function f(x) = 31x + 71

Solve this problem<br> PLS SOLVE ASAP!!

guajiro [1.7K]

α $a^{2} (-4+6)$

8 0

3 years ago

I have the equations 8x + 3y = 20.50 and 4x + 5y = 22.50<br> How do I solve for x and y?

snow_tiger [21]

8x + 3y = 20.50
-
4x+5y=22.50
=
4x-2y=-2, so you have to divide each number by 2, then
2x-y=-1, so

-y=-1-2x /-1, y=1+2x, then replace it with one original equation like the first one for instance:
8x+3(1+2x)=20.50, then
8x+3+6x=20.50, then
14x=20.50-3
14x=17.5
x=1.25, then solve y:\
y=1+2*(1.25)
y=1+2.5
y=3.5,
So answer is x=1.25, and y=3.5

6 0

3 years ago

The mean time it takes to walk to the bus stop is 8 minutes (with a standard deviation of 2 minutes) and the mean time it takes

kifflom [539]

We have been given for a normal distribution the mean time it takes to walk to the bus stop is 8 minutes with a standard deviation of 2 minutes. And the mean time it takes for the bus to get to school is 20 minutes with a standard deviation of 4 minutes.

(a) Average time that it would take reach school can be obtained by adding the average times.

8+20 = 28 minutes.

(b) Standard deviation of the trip to school can be found as:

$\sigma =\sqrt{2^{2}+4^{2}}=\sqrt{4+16}=\sqrt{20}=4.47$

Therefore, standard deviation of the entire trip is 4.47 minutes.

(c) Let us first find z score corresponding to 30 minutes. $z=\frac{x-\mu }{\sigma }=\frac{30-28}{4.47}=0.447$

We need to find the probability such that $P(x>30)=P(z>0.447)=0.67$

Therefore, the required probability is 0.67.

(d) If average time to walk to school is 10 minutes, then overall average time for the trip will be 10+20 = 30 minutes.

(e) Standard deviation won't change it will remain 4.47

(f) The new probability will be:

$z=\frac{x-\mu }{\sigma }=\frac{30-90}{4.47}=0$

$P(x>30)=P(z>0)=0.5$

Therefore, probability will be 0.50.

6 0

3 years ago

Read 2 more answers

Talia has a square bedroom. Her family is moving and her bedroom in her new apartment will be 3 feet shorter in one direction an

djverab [1.8K]

Answer (x represents the first direction and the y represents the second direction):

(x - 3) × (y + 5)
New bedroom: 7 ft × 15 ft. Her new bedroom is 5 sq. ft larger than her old bedroom

I hope this helps!

3 0

3 years ago

The ratio of boys to girls in a class is 4 : 5

Fofino [41]

Answer: 4/9 of the class are boys and 5/9 of the class are girls.

Step-by-step explanation:

There are 9 nine students in total in the class since 4 + 5 = 9.
Input the amount of boys and girls there are in the class in the numerator and have 9 as the denominator. 4/9 of the class are boys and 5/9 of the class are girls.

7 0

3 years ago

Read 2 more answers

Find the domain and range of the following function f(x) = 31x + 71 - 2?