Question

Solve using elimination.

5x-4y=-21
-2x+4y=18

Answer 1

(-1,4)

x=-1,y=4

Explanation:

To solve by elimination, add the two equations together to eliminate y.

5x-4y=-21

-2x+4y=18

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3x = -3

Divide by 3

3x/3 = -3/3

x=-1

Now we still need to find y

-2x + 4y = 18

-2(-1) +4y =18

2+4y =18

Subtract 2 from each side

-2+2 + 4y = 18-2

4y = 16

Divide by 4

4y/4 = 16/4

y =4