(a+2a-9)(a+3)=

Solution for (a+2a-9)(a+3)= equation:

Simplifying
(a + 2a + -9)(a + 3) = 0

Reorder the terms:
(-9 + a + 2a)(a + 3) = 0

Combine like terms: a + 2a = 3a
(-9 + 3a)(a + 3) = 0

Reorder the terms:
(-9 + 3a)(3 + a) = 0

Multiply (-9 + 3a) * (3 + a)
(-9(3 + a) + 3a * (3 + a)) = 0
((3 * -9 + a * -9) + 3a * (3 + a)) = 0
((-27 + -9a) + 3a * (3 + a)) = 0
(-27 + -9a + (3 * 3a + a * 3a)) = 0
(-27 + -9a + (9a + 3a2)) = 0

Combine like terms: -9a + 9a = 0
(-27 + 0 + 3a2) = 0
(-27 + 3a2) = 0

Solving
-27 + 3a2 = 0

Solving for variable 'a'.

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

Add '27' to each side of the equation.
-27 + 27 + 3a2 = 0 + 27

Combine like terms: -27 + 27 = 0
0 + 3a2 = 0 + 27
3a2 = 0 + 27

Combine like terms: 0 + 27 = 27
3a2 = 27

Divide each side by '3'.
a2 = 9

Simplifying
a2 = 9

Take the square root of each side:
a = {-3, 3}