Answers:
The value of x in terms of b is x = -3/b
The value of x when b is 3 is x = -1
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Work Shown:
Let's isolate x
-2(bx - 5) = 16
bx - 5 = 16/(-2) ... dividing both sides by -2
bx - 5 = -8
bx = -8+5 ... adding 5 to both sides
bx = -3
x = -3/b ... dividing both sides by b
That wraps up the first part.
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To answer the second part, we plug in b = 3 to get
x = -3/b
x = -3/3
x = -1