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27 votes
27 votes
4x+8y=20, -4x+2y=-30

User Gregsonian
by
2.6k points

1 Answer

7 votes
7 votes

Answer:

(7, - 1 )

Explanation:

4x + 8y = 20 → (1)

- 4x + 2y = - 30 → (2)

adding the 2 equations term by term eliminates x

0 + 10y = - 10

10y = - 10 ( divide both sides by 10 )

y = - 1

substitute y = - 1 into either of the 2 equations and solve for x

substituting into (1)

4x + 8(- 1) = 20

4x - 8 = 20 ( add 8 to both sides )

4x = 28 ( divide both sides by 4 )

x = 7

solution is (7, - 1 )

User Fredrik Kalseth
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3.1k points