12a+4b-3(a-b)=

Solution for 12a+4b-3(a-b)= equation:

Simplifying
12a + 4b + -3(a + -1b) = 0
12a + 4b + (a * -3 + -1b * -3) = 0
12a + 4b + (-3a + 3b) = 0

Reorder the terms:
12a + -3a + 4b + 3b = 0

Combine like terms: 12a + -3a = 9a
9a + 4b + 3b = 0

Combine like terms: 4b + 3b = 7b
9a + 7b = 0

Solving
9a + 7b = 0

Solving for variable 'a'.

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

Add '-7b' to each side of the equation.
9a + 7b + -7b = 0 + -7b

Combine like terms: 7b + -7b = 0
9a + 0 = 0 + -7b
9a = 0 + -7b
Remove the zero:
9a = -7b

Divide each side by '9'.
a = -0.7777777778b

Simplifying
a = -0.7777777778b