-63-15=13a

Solution for -63-15=13a equation:

Simplifying
-63 + -15 = 13a

Combine like terms: -63 + -15 = -78
-78 = 13a

Solving
-78 = 13a

Solving for variable 'a'.

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

Add '-13a' to each side of the equation.
-78 + -13a = 13a + -13a

Combine like terms: 13a + -13a = 0
-78 + -13a = 0

Add '78' to each side of the equation.
-78 + 78 + -13a = 0 + 78

Combine like terms: -78 + 78 = 0
0 + -13a = 0 + 78
-13a = 0 + 78

Combine like terms: 0 + 78 = 78
-13a = 78

Divide each side by '-13'.
a = -6

Simplifying
a = -6