Answer with a detailed explanation. you!

This answer is 8

Step-by-step explanation:

It actually is very simple. For this question you do not even need the g(x) equation to continue, so put it aside for now. F(x) means that whatever number that will take the place of x will be used in this equation. If f(x)=3x-1, then f(3)=3(3)-1

This happens because the 3 in f(3 tells you to substitute x for 3 in the equation. ) So just plug in 3 for x and solve to get the answer 8.

(b) 240

step-by-step explanation:

first, we use the pythagorean formula using the given side lengths to find x. then we use x to find the side lengths. then we add the side lengths to find the perimeter.

pythagorean theorem formula:

a^2 + b^2 = c^2

(x - 20)^2 + (x - 40)^2 = x^2

x^2 - 40x + 400 + x^2 - 80x + 1600 = x^2

x^2 -120x + 2000 = 0

(x - 100)(x - 20) = 0

x - 100 = 0 or x - 20 = 0

x = 100 or x = 20

we see that the solution x = 20 must be discarded because it will give a negative side length and a side length of 0. the only valid solution is x = 100.

perimeter = sum of the lengths of the sides

perimeter = x + x - 20 + x - 40

perimeter = 3x - 60

replace x with 100.

perimeter = 3(100) - 60

perimeter = 300 - 60

perimeter = 240