6+7a=-3+4a-9

Solution for 6+7a=-3+4a-9 equation:

Simplifying
6 + 7a = -3 + 4a + -9

Reorder the terms:
6 + 7a = -3 + -9 + 4a

Combine like terms: -3 + -9 = -12
6 + 7a = -12 + 4a

Solving
6 + 7a = -12 + 4a

Solving for variable 'a'.

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

Add '-4a' to each side of the equation.
6 + 7a + -4a = -12 + 4a + -4a

Combine like terms: 7a + -4a = 3a
6 + 3a = -12 + 4a + -4a

Combine like terms: 4a + -4a = 0
6 + 3a = -12 + 0
6 + 3a = -12

Add '-6' to each side of the equation.
6 + -6 + 3a = -12 + -6

Combine like terms: 6 + -6 = 0
0 + 3a = -12 + -6
3a = -12 + -6

Combine like terms: -12 + -6 = -18
3a = -18

Divide each side by '3'.
a = -6

Simplifying
a = -6