SOLUTION: solve each system by the substitution method. Be sure to check all proposed solutions. -4x+y=-11 2x-3y=5

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Question 189289: solve each system by the substitution method. Be sure to check all proposed solutions.
-4x+y=-11
2x-3y=5
Answer by jojo14344(1513) About Me  (Show Source):
You can put this solution on YOUR website!


Given:system%28-4x%2By=-11%28EQN1%29%2C2x-3y=5%28EQN2%29%29

Isolate "y" in EQN 1 ,y=4x-11, EQN 3 (subst. in EQN 2)

2x-3%28highlight%284x-11%29%29=5
2x-12x%2B33=5
-10x=5-33
-10x=-28 -----> cross%28-10%29x%2Fcross%28-10%29=cross%28-28%292.8%2Fcross%28-10%29
red%28x=2.8%29, subst. in EQN 3

y=4%28highlight%282.8%29%29-11=11.2-11=red%280.2%29

Let's check, subst. (x,y) = (2.8,0.20) in EQN 1:
-4%282.8%29%2B0.20=-11
-11.2%2B0.20=-11
-11=-11, good

Subst. (x,y)=(2.8,0.20) in EQN 2:
2%282.8%29-3%280.20%29=5
5.6-0.60=5
5=5, good.

These two lines intersect @ point (2.8, 0.2)

Let's see the graph,
--->RED, EQN 1; GREEN, EQN 2

Thank you,
Jojo