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Can someone solve this and show it step by step

3(x + 1) − 5(y + 2) = 12
5(−3 + 2x) − 3(4 − y) = −3

1 Answer

4 votes

Answer:

x = 3, y = - 2

Explanation:

Simplify the 2 given equations

3(x + 1) - 5(y + 2) = 12 ← distribute left side

3x + 3 - 5y - 10 = 12

3x - 5y - 7 = 12 ( add 7 to both sides )

3x - 5y = 19 → (1)

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5(- 3 + 2x) - 3(4 - y) = - 3 ← distribute left side

- 15 + 10x - 12 + 3y = - 3

10x + 3y - 27 = - 3 ( add 27 to both sides )

10x + 3y = 24 → (2)

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Solve the 2 equations simultaneously

3x - 5y = 19 → (1)

10x + 3y = 24 → (2)

Multiplying (1) by 3 and (2) by 5 and adding the result will eliminate y

9x - 15y = 57 → (3)

50x + 15y = 120 → (4)

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

59x = 177 ( divide both sides by 59 )

x = 3

Substitute x = 3 into either of the 2 equations and solve for y

Substituting into (1)

3(3) - 5y = 19

9 - 5y = 19 ( subtract 9 from both sides )

- 5y = 10 ( divide both sides by - 5 )

y = - 2

Solution is x = 3, y = - 2

User Stephen Sorensen
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