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How to solve 3x-2y=14 and 5x+6y=42 using substitution

User Sauceboat
by
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1 Answer

1 vote

Answer:

(6, 2 )

Explanation:

3x - 2y = 14 → (1)

5x + 6y = 42 → (2)

multiply (1) through by - 1

- 3x + 2y = - 14 ( add 3x to both sides )

2y = 3x - 14

substitute 2y = 3x - 14 into (2)

5x + 3(2y) = 42

5x + 3(3x - 14) = 42

5x + 9x - 42 = 42

14x - 42 = 42 ( add 42 to both sides )

14x = 84 ( divide both sides by 14 )

x = 6

substitute x = 6 into either of the 2 equations and solve for y

substituting into (2)

5(6) + 6y = 42

30 + 6y = 42 ( subtract 30 from both sides )

6y = 12 ( divide both sides by 6 )

y = 2

solution is (6, 2 )

User Mayowa
by
7.2k points