To solve the equation -4x + 12 = 8x - 3, we need to isolate the variable x.

First, let's simplify both sides of the equation by combining like terms:

-4x + 12 = 8x - 3

To get rid of the variable on the right side, we can subtract 8x from both sides:

-4x - 8x + 12 = -3

Combining like terms:

-12x + 12 = -3

Next, let's isolate the variable by subtracting 12 from both sides:

-12x + 12 - 12 = -3 - 12

Simplifying:

-12x = -15

Finally, to solve for x, we divide both sides by -12:

(-12x) / -12 = (-15) / -12

Simplifying:

x = 5/4 or 1.25

Therefore, the solution to the equation -4x + 12 = 8x - 3 is x = 5/4 or 1.25.