(7a+9)(-1a+6)=

Solution for (7a+9)(-1a+6)= equation:

Simplifying
(7a + 9)(-1a + 6) = 0

Reorder the terms:
(9 + 7a)(-1a + 6) = 0

Reorder the terms:
(9 + 7a)(6 + -1a) = 0

Multiply (9 + 7a) * (6 + -1a)
(9(6 + -1a) + 7a * (6 + -1a)) = 0
((6 * 9 + -1a * 9) + 7a * (6 + -1a)) = 0
((54 + -9a) + 7a * (6 + -1a)) = 0
(54 + -9a + (6 * 7a + -1a * 7a)) = 0
(54 + -9a + (42a + -7a2)) = 0

Combine like terms: -9a + 42a = 33a
(54 + 33a + -7a2) = 0

Solving
54 + 33a + -7a2 = 0

Solving for variable 'a'.

Factor a trinomial.
(6 + -1a)(9 + 7a) = 0

Subproblem 1
Set the factor '(6 + -1a)' equal to zero and attempt to solve:

Simplifying
6 + -1a = 0

Solving
6 + -1a = 0

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

Add '-6' to each side of the equation.
6 + -6 + -1a = 0 + -6

Combine like terms: 6 + -6 = 0
0 + -1a = 0 + -6
-1a = 0 + -6

Combine like terms: 0 + -6 = -6
-1a = -6

Divide each side by '-1'.
a = 6

Simplifying
a = 6
Subproblem 2
Set the factor '(9 + 7a)' equal to zero and attempt to solve:

Simplifying
9 + 7a = 0

Solving
9 + 7a = 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 + 7a = 0 + -9

Combine like terms: 9 + -9 = 0
0 + 7a = 0 + -9
7a = 0 + -9

Combine like terms: 0 + -9 = -9
7a = -9

Divide each side by '7'.
a = -1.285714286

Simplifying
a = -1.285714286
Solution
a = {6, -1.285714286}