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How to solve by Substitution these nu
mbers x-6y=15 and 6x+5y=8

User Lavvo
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1 Answer

2 votes

Answer:

(3, - 2 )

Explanation:

Given the 2 equations

x - 6y = 15 → (1)

6x + 5y = 8 → (2)

Rearrange (1) expressing x in terms of y by adding 6y to both sides

x = 15 + 6y → (3)

Substitute x = 15 + 6y into (2)

6(15 + 6y) + 5y = 8 ← distribute and simplify left side

90 + 36y + 5y = 8

90 + 41y = 8 ( subtract 90 from both sides )

41y = - 82 ( divide both sides by 41 )

y = - 2

Substitute y = - 2 into (3) for corresponding value of x

x = 15 + 6(- 2) = 15 - 12 = 3

Solution is (3, - 2 )

User Fresa
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