Question

What is the value of b? –7b = –42

Answer 1

$-7b = -42\\\\b = \frac{-42}{-7}\\\\\boxed{\bf{b = 6}}$

Answer 2

For this question you can just divide the both sides by -7 so you gonna have : 
-7b/-7 = -42/-7 ⇒ b = 6 :)))
i hope this is helpful 
have a nice day