Answer:
[tex]b= \frac{q - 4a}{4} [/tex]
Step-by-step explanation:
ill suppose that you mean : "solve for b" not for d, since there is no d term in the formula given. So:
[tex]q = 4(a + b) \\ q = 4a + 4b \\ 4a + 4b = q \\ 4a + 4b - 4a = q - 4a \\ 4b = q - 4a \\ b = \frac{q - 4a}{4} [/tex]
