4a+6+6=-21

Solution for 4a+6+6=-21 equation:

Simplifying
4a + 6 + 6 = -21

Reorder the terms:
6 + 6 + 4a = -21

Combine like terms: 6 + 6 = 12
12 + 4a = -21

Solving
12 + 4a = -21

Solving for variable 'a'.

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

Add '-12' to each side of the equation.
12 + -12 + 4a = -21 + -12

Combine like terms: 12 + -12 = 0
0 + 4a = -21 + -12
4a = -21 + -12

Combine like terms: -21 + -12 = -33
4a = -33

Divide each side by '4'.
a = -8.25

Simplifying
a = -8.25