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Please help with substitution!

Please help with substitution!-example-1
User Brezhnews
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1 Answer

5 votes

2. If
y=2x+11, then in the second equation we'd get


y+x=5\implies(2x+11)+x=5\implies3x+11=5\implies3x=-6\implies x=-2

Then we get
y=2(-2)+11=7.

3. If
-5x+y=-1, then
y=5x-1, and substituting this into the second equation gives


y-4x=-3\implies(5x-1)-4x=-3\implies x-1=-3\implies x=-2

which gives


y=5(-2)-1=-11

User Sebastien D
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