Which are the solutions of x2 = –5x + 8?

Rewrite the equation set = to 0.
x^2 + 5x - 8 = 0
The quadratic will not factor so you have to use the quadratic formula.
x = (-b + - sqrt(b^2 - 4ac))/2a
x = (5 + - sqrt(25 - 4* 1* -8))/2
x = (5 + - sqrt 57)/2