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Solve the systems by the addition method: {x-2y = -4 2x + y = 7

1 Answer

2 votes

Answer:

(2, 3 )

Explanation:

Given the 2 equations

x - 2y = - 4 → (1)

2x + y = 7 → (2)

Multiplying (2) by 2 and adding to (1) will eliminate the y- term

4x + 2y = 14 → (3)

Add (1) and (3) term by term to eliminate y, that is

5x = 10 ( divide both sides by 5 )

x = 2

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

Substituting into (2)

2(2) + y = 7

4 + y = 7 ( subtract 4 from both sides )

y = 3

Solution is (2, 3 )

User Eduardo Chavira
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