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Solve the system of equations: 10x + 7y = 49 and 10y – x = 70

User Chris Page
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1 Answer

6 votes
10x + 7y = 49
10y – x = 70 so x = 10y - 70

substitute
x = 10y - 70 into 10x + 7y = 49
10x + 7y = 49
10(10y - 70) + 7y = 49
100y - 700 + 7y = 49
107y = 749
y = 7

x = 10y - 70 = 10(7) - 70 = 0

answer
(0, 7)

hope it helps
User Gcandal
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