3(a+4)-6(a-3)=105

Solution for 3(a+4)-6(a-3)=105 equation:

Simplifying
3(a + 4) + -6(a + -3) = 105

Reorder the terms:
3(4 + a) + -6(a + -3) = 105
(4 * 3 + a * 3) + -6(a + -3) = 105
(12 + 3a) + -6(a + -3) = 105

Reorder the terms:
12 + 3a + -6(-3 + a) = 105
12 + 3a + (-3 * -6 + a * -6) = 105
12 + 3a + (18 + -6a) = 105

Reorder the terms:
12 + 18 + 3a + -6a = 105

Combine like terms: 12 + 18 = 30
30 + 3a + -6a = 105

Combine like terms: 3a + -6a = -3a
30 + -3a = 105

Solving
30 + -3a = 105

Solving for variable 'a'.

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

Add '-30' to each side of the equation.
30 + -30 + -3a = 105 + -30

Combine like terms: 30 + -30 = 0
0 + -3a = 105 + -30
-3a = 105 + -30

Combine like terms: 105 + -30 = 75
-3a = 75

Divide each side by '-3'.
a = -25

Simplifying
a = -25