Answer:
x=9 or -25
Step-by-step explanation:
Simplifying
x2 + 16x = 225
Reorder the terms:
16x + x2 = 225
Solving
16x + x2 = 225
Solving for variable 'x'.
Reorder the terms:
-225 + 16x + x2 = 225 + -225
Combine like terms: 225 + -225 = 0
-225 + 16x + x2 = 0
Factor a trinomial.
(-25 + -1x)(9 + -1x) = 0
Subproblem 1
Set the factor '(-25 + -1x)' equal to zero and attempt to solve:
Simplifying
-25 + -1x = 0
Solving
-25 + -1x = 0
Move all terms containing x to the left, all other terms to the right.
Add '25' to each side of the equation.
-25 + 25 + -1x = 0 + 25
Combine like terms: -25 + 25 = 0
0 + -1x = 0 + 25
-1x = 0 + 25
Combine like terms: 0 + 25 = 25
-1x = 25
Divide each side by '-1'.
x = -25
Simplifying
x = -25
Subproblem 2
Set the factor '(9 + -1x)' equal to zero and attempt to solve:
Simplifying
9 + -1x = 0
Solving
9 + -1x = 0
Move all terms containing x to the left, all other terms to the right.
Add '-9' to each side of the equation.
9 + -9 + -1x = 0 + -9
Combine like terms: 9 + -9 = 0
0 + -1x = 0 + -9
-1x = 0 + -9
Combine like terms: 0 + -9 = -9
-1x = -9
Divide each side by '-1'.
x = 9
Simplifying
x = 9
Solution
x = {-25, 9}
