Question

A printing company uses the formula C = 0.5x + 10 to find the cost of printing x business cards.

Which equation correctly solves the formula for x?
A) x = 2C - 20
B) x = -2C + 20
C) x = C + 10/0.5
D) x = C - 0.5/10

Answer 1

The correct answer for USA Test prep is 2C-20 (Answer A)

Answer 2

c = 0.5x + 10

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Switch side :
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0.5x + 10 = c

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Take away 10 from both sides :
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0.5x = c - 10

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Multiply by 2 through :
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x = 2c - 20

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Answer : x = 2c - 20 (Answer A)
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