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30 votes
Solve the following system by the substitution method. Check the solution(s)

7x + 4y = 10
x+y=1

User Volhv
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1 Answer

21 votes
21 votes

Answer:

x = 2; y = -1

Explanation:

We can solve (first for y, then for x) using substitution:


x+y=1\\7x+4y=10\\(x+y=1)-y\\x=1-y\\\\7(1-y)+4y=10\\7-7y+4y=10\\(7-3y=10)-7\\(-3y=3)/-3\\y=-1\\\\(x-1=1)+1\\x=2

User Object Object
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