Answer:
b = -4
Step-by-step explanation:
-21 = 4b + 19 - ( -6b)
Switch sides.
4b + 19 - (-6b) = -21
Apply rule - (-a) = a
4b + 19 + 6b = -21
Group like terms.
10b + 19 = -21
Subtract 19 from both sides.
10b + 19 - 19 = -21 -19
Simplify.
10b = -40
Divide both sides by 10.
[tex]\frac{10b}{10} =\frac{-40}{10}[/tex]
Simplify.
b = -4
