Answer:
x=20
Step-by-step explanation:
The Pythagorean theorem is
a^2 +b^2 = c^2
where a and b are the legs and c is the hypotenuse.
The legs are x and 15 and the hypotenuse is 25
x^2 + 15^2 = 25^2
x^2 +225 = 625
Subtract 225 from each side
x^2 +225-225 = 625-225
x^2 = 400
Take the square root of each side
sqrt(x^2) = sqrt(400)
x = 20
So we want to know which of the following functions has an inverse function. So an inverse function is a function that "reverses" another function. We need to put y instead of x and x instead of y. So for the first case: y=x is x=y so this function has an inverse function. y=x^2 is x=y^2 so y=sqrt(x). y=x^3 is x=y^3 so y=∛x. y=x^4 so x=y^4, y=4√x or forth root of x. So all of our functions have an inverse function.
It is the graph where the two lines intersect, when they intersect there is a point where they connect, and that is your answer
