x2+16x-225=0

Solve for x:
x^2 + 16 x - 225 = 0

The left hand side factors into a product with two terms:
(x - 9) (x + 25) = 0

Split into two equations:
x - 9 = 0 or x + 25 = 0

Add 9 to both sides:
x = 9 or x + 25 = 0

Subtract 25 from both sides:
Answer: |x = 9              or               x = -25

x^2 + 16x  - 225 = 0           factor

(x + 25) (x  − 9 )  =  0

Set each factor to 0

x + 25  = 0  →  x  = − 25          or            x  −  9  = 0  →   x  = 9

x²+16x-225=0

(x-9)(x+25)

x=9,-25