Question 553033
solve using addition to eliminate one variable. 

1. -y=2x, 3x+y+20
The 2nd eqn has no equal sign.
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2. 4x+2y=6, 2x+y=3
The 1st eqn is 2 times the 2nd.
--> dependent, an infinite # of solutions.
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Solve using Substitution to eliminate one variable.

3. y+5x=17, 4x-3y=6
y = -5x+17
Sub for y in the 2nd eqn
4x - 3(-5x+17) = 6
19x - 51 = 6
x = 3
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y = -5x+17
y = 2
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4. y+-x+3, 2x=-2y+10
1st eqn has no equal sign.