what is x squared plus 15 equals -8x

Answer 1

X^2 + 15 = -8X

X^2 + 8X + 15 = 0 Adding 8X to both sides.

(X + 5) (X + 3) = 0 Factoring

X + 5 = 0 AND X + 3 = 0

X = -5 AND X = -3

CHECKING

Plug -5 into "X".

x^2 + 15 = (-5)(-5) + 15 = 25 + 15 = 40

-8X = (-8) (-5) = 40

Plug -3 into "X".

X^2 + 15 = (-3) (-3) + 15 = 9 + 15 = 24

-8X = (-8) (-3) = 24

Hope this helped Jennissa.