(7b-9)-3(2b+4)=-4

Solution for (7b-9)-3(2b+4)=-4 equation:

Simplifying
(7b + -9) + -3(2b + 4) = -4

Reorder the terms:
(-9 + 7b) + -3(2b + 4) = -4

Remove parenthesis around (-9 + 7b)
-9 + 7b + -3(2b + 4) = -4

Reorder the terms:
-9 + 7b + -3(4 + 2b) = -4
-9 + 7b + (4 * -3 + 2b * -3) = -4
-9 + 7b + (-12 + -6b) = -4

Reorder the terms:
-9 + -12 + 7b + -6b = -4

Combine like terms: -9 + -12 = -21
-21 + 7b + -6b = -4

Combine like terms: 7b + -6b = 1b
-21 + 1b = -4

Solving
-21 + 1b = -4

Solving for variable 'b'.

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

Add '21' to each side of the equation.
-21 + 21 + 1b = -4 + 21

Combine like terms: -21 + 21 = 0
0 + 1b = -4 + 21
1b = -4 + 21

Combine like terms: -4 + 21 = 17
1b = 17

Divide each side by '1'.
b = 17

Simplifying
b = 17