Question

Choose the inverse of y=x^2-10

Answer 1

x = 5 + sqrt(y+25), for x>=5

x = 5 - sqrt(y+25), for x<=5

Explanation:

y = x^2 - 10x + 25 - 25

y = (x-5)^2 - 25

y+25 = (x-5)^2

x-5 = +/-sqrt(y+25)

And you get TWO inverses:

x = 5 + sqrt(y+25), for x>=5

x = 5 - sqrt(y+25), for x<=5