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1 vote
3. 2x – y = -7

4x – y = -4
A) (-1.5, 4)
B) (1.5, 10)
C) (4, -1.5)
D) (-1.5, -2)

1 Answer

2 votes
multiply first equaton by -1 and add to first

-2x+y=7
4x-y=-4 +
2x+0y=3

2x=3
divide 2
x=3/2

sub
2x-y=-7
2(3/2)-y=-7
3-y=-7
minus 3
-y=-10
negative 1 times both sides
y=10

(3/2,10)
(1.5,10)

B is ansre
User Alex Fedoseev
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9.3k points

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