Question

What is the value of z so that -9 and 9 are both solutions of x^2+z=103?

a.-22
b.3
c.22
d.184

Answer 1

The answer is C.
x^2 + z = 103x^2 + 22 = 103*Subtract both sides by 22*x^2 + 22 - 22 = 103 - 22x^2 = 81*square root both sides to find x*√x^2 = √81
x = +- 9