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If x+2y=14 and x-y=5, find x.

A6

B4

C8

D10

Answer:

C. 8

Read Explanation:

We have:

x+2y=14x + 2y = 14
xy=5x - y = 5

From the second equation:

x=y+5x = y + 5

Substitute into the first equation:

(y+5)+2y=14(y+5) + 2y = 14
3y+5=143y + 5 = 14
3y=93y = 9
y=3y = 3

Now,

x=y+5=3+5=8x = y + 5 = 3 + 5 = 8

Therefore,

8\boxed{8}


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