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3 years ago

Solve using elimination. 4x + y = -5 8x + 3y = -19 Plz I need help

Mathematics

1 answer:

Debora [2.8K]3 years ago

7 0

Answer:

(1, -9)

Step-by-step explanation:

4x + y = -5

8x + 3y = -19

If we have to use elimination, that means we're going to add or subtract these two whole equations by each other so that we can cancel out one of the variables.

I think that we could easily turn 4x into 8x if we multiply the top equation by 2.

4x + y = -5 ---> 8x + 2y = -10

Now put them next to each other, and subtract to get rid of the xs.

8x + 2y = -10

- 8x + 3y = -19

------------------------

0x - y = -10 - -19

-y = 9

y = -9

Plug this back in to get x.

4x + y = -5

4x - 9 = -5

4x = -5 - -9

4x = 4

x = 1

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