(2a-1)(a+9)=

Solution for (2a-1)(a+9)= equation:

Simplifying
(2a + -1)(a + 9) = 0

Reorder the terms:
(-1 + 2a)(a + 9) = 0

Reorder the terms:
(-1 + 2a)(9 + a) = 0

Multiply (-1 + 2a) * (9 + a)
(-1(9 + a) + 2a * (9 + a)) = 0
((9 * -1 + a * -1) + 2a * (9 + a)) = 0
((-9 + -1a) + 2a * (9 + a)) = 0
(-9 + -1a + (9 * 2a + a * 2a)) = 0
(-9 + -1a + (18a + 2a2)) = 0

Combine like terms: -1a + 18a = 17a
(-9 + 17a + 2a2) = 0

Solving
-9 + 17a + 2a2 = 0

Solving for variable 'a'.

Factor a trinomial.
(-9 + -1a)(1 + -2a) = 0

Subproblem 1
Set the factor '(-9 + -1a)' equal to zero and attempt to solve:

Simplifying
-9 + -1a = 0

Solving
-9 + -1a = 0

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

Add '9' to each side of the equation.
-9 + 9 + -1a = 0 + 9

Combine like terms: -9 + 9 = 0
0 + -1a = 0 + 9
-1a = 0 + 9

Combine like terms: 0 + 9 = 9
-1a = 9

Divide each side by '-1'.
a = -9

Simplifying
a = -9
Subproblem 2
Set the factor '(1 + -2a)' equal to zero and attempt to solve:

Simplifying
1 + -2a = 0

Solving
1 + -2a = 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 + -2a = 0 + -1

Combine like terms: 1 + -1 = 0
0 + -2a = 0 + -1
-2a = 0 + -1

Combine like terms: 0 + -1 = -1
-2a = -1

Divide each side by '-2'.
a = 0.5

Simplifying
a = 0.5
Solution
a = {-9, 0.5}