Question 807784
let number be x
2 times a number = 2x
7 added to it
2x+7

square of number = x^2
8 less
x^2-8

2x+7 = x^2-8

x^2-2x-15=0

x^2-5x+3x-15=0
x(x-5)+3(x-5)=0

(x-5)(x+3)=0

x=5 OR x=-3