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If x + y = 12 and 3x - y = 20, find the value of 2x - y

If x + y = 12 and 3x - y = 20, find the value of 2x - y

A.

8

B.

10

C.

12

D.

15

View answer & explanation

Correct answer is C

x + y = 12 + 3x - y = 20 --------------- 4x = 32 x = 8 x + y = 12; 8 + y = 12; y = 12 - 8 = 4 2x - y = 2(8) - 4; 16 - 4 = 12

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