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5 votes
Solve for x: 1/4 (x-7) = 2x

A) x= 9
B) x= 1
C) x= -1
D) x= 15​

User Alanionita
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1 Answer

4 votes
C) x = -1

Steps:

1/4 (x - 7) = 2x (distribute 1/4 with x and -7)

1/4x - 7/4 = 2x (distributed)

1/4x - 7/4 - 2x = 0 (put all values on 1 side)

1/4 x - 2x = 7/4 (put the x values together and 7/4 on the other side. *make sure you switch the signs (+ & -) when moving the values to the other side of the equal sign)

1/4x - 8/4x = 7/4 (multiply 2x by 4 on on top and bottom. *2x written as fraction is 2x/1)

-7/4 x = 7/4 (when you subtract 1/4x with 8/4x you get -7/4)

(-7/4)x / (-7/4) = 7/4 / (-7/4) (divide both sides by -7/4 to solve for x)

X = -1

Reminders when multiplying or dividing:

2 positives make a positive

2 negatives make a positive

A positive and a negative make a negative

A negative and a positive make a negative

User Ahmad Ali
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5.1k points