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3 years ago

Help ! solve the following system of equations -9x+2y=-13 2x-9y=20

Mathematics

1 answer:

Stella [2.4K]3 years ago

5 0

Answer: x = 1, y = -2

Step-by-step explanation:

-9x+2y=-13

x= 13/9 + 2/9y

2x-9y=20

2(13/9+2/9y)-9y=20

Substitute y with -2.

x= 13/9+2/9(-2)

After solving you'll see that 1 is a possible solution for x.

Check your answer

-9x+2y=-13

-9x1+2(-2) = -13

2x-9y=20

2x1-9(-2) = 20

-13 = -13

20 = 20

Therefore, x=1 and y=-2

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