# Math

posted by Will

Given that: 4x – y + 9 = 0 and 3y – 2x = 7, solve for x.
does x=-2?

1. Steve

Yes. Could you not check your answer to see whether it fit the equations? That's faster than posting here and waiting for an answer.

2. Reiny

from the first: y = 4x+9
sub into the 2nd:
3(4x+9) - 2x = 7
12x + 27 - 2x = 7
10x = -20
x = -2

you had that, but you only found x, you must also find y

sub x = -2 into y = 4x+9
y = -8+9 = 1

x = -2, y = 1

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