a^2-15a-16=0

Solution for a^2-15a-16=0 equation:

Simplifying
a2 + -15a + -16 = 0

Reorder the terms:
-16 + -15a + a2 = 0

Solving
-16 + -15a + a2 = 0

Solving for variable 'a'.

Factor a trinomial.
(-1 + -1a)(16 + -1a) = 0

Subproblem 1
Set the factor '(-1 + -1a)' equal to zero and attempt to solve:

Simplifying
-1 + -1a = 0

Solving
-1 + -1a = 0

Move all terms containing a to the left, all other terms to the right.

Add '1' to each side of the equation.
-1 + 1 + -1a = 0 + 1

Combine like terms: -1 + 1 = 0
0 + -1a = 0 + 1
-1a = 0 + 1

Combine like terms: 0 + 1 = 1
-1a = 1

Divide each side by '-1'.
a = -1

Simplifying
a = -1
Subproblem 2
Set the factor '(16 + -1a)' equal to zero and attempt to solve:

Simplifying
16 + -1a = 0

Solving
16 + -1a = 0

Move all terms containing a to the left, all other terms to the right.

Add '-16' to each side of the equation.
16 + -16 + -1a = 0 + -16

Combine like terms: 16 + -16 = 0
0 + -1a = 0 + -16
-1a = 0 + -16

Combine like terms: 0 + -16 = -16
-1a = -16

Divide each side by '-1'.
a = 16

Simplifying
a = 16
Solution
a = {-1, 16}