69=-3+6(3a+6)

Solution for 69=-3+6(3a+6) equation:

Simplifying
69 = -3 + 6(3a + 6)

Reorder the terms:
69 = -3 + 6(6 + 3a)
69 = -3 + (6 * 6 + 3a * 6)
69 = -3 + (36 + 18a)

Combine like terms: -3 + 36 = 33
69 = 33 + 18a

Solving
69 = 33 + 18a

Solving for variable 'a'.

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

Add '-18a' to each side of the equation.
69 + -18a = 33 + 18a + -18a

Combine like terms: 18a + -18a = 0
69 + -18a = 33 + 0
69 + -18a = 33

Add '-69' to each side of the equation.
69 + -69 + -18a = 33 + -69

Combine like terms: 69 + -69 = 0
0 + -18a = 33 + -69
-18a = 33 + -69

Combine like terms: 33 + -69 = -36
-18a = -36

Divide each side by '-18'.
a = 2

Simplifying
a = 2