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3 years ago

Solve system of equations for x + y: 3x + 2y = -18 & 2x + 9y =-12

Mathematics

1 answer:

blondinia [14]3 years ago

3 0

Answer:

(- 6, 0 )

Step-by-step explanation:

Given the 2 equations

3x + 2y = - 18 → (1)

2x + 9y = - 12 → (2)

Multiplying (1) by 2 and (2) by - 3 and adding will eliminate the term in x, that is

6x + 4y = - 36 → (3)

- 6x - 27y = 36 → (4)

Add (3) and (4) term by term to eliminate x

- 23y = 0

y = 0

Substitute y = 0 into either of the 2 equations and evaluate for x

Substituting into (1)

3x + 0 = - 18

3x = - 18 ( divide both sides by 3 )

x = - 6

Solution is (- 6, 0 )

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