SOLUTION: Use substitution to solve the system. x - 7y = -10 3x + 2y = 10

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Question 159754: Use substitution to solve the system.
x - 7y = -10
3x + 2y = 10
Answer by KnightOwlTutor(293) About Me  (Show Source):
You can put this solution on YOUR website!
x - 7y = -10
Add 7y to both sides
x=-10+7Y
replace x in the second equation with -10+7Y
3(-10+7Y)+2Y=10
Use the distributive property
-30+21Y+2Y=10
-30+23Y=10
add 30 to both sides of the equation
23Y=40
divide both sides by 23
Y=40/23
Replace y with 40/23 in the following equation in order to get a value for X
x - 7y = -10
x-7(40/23)=-10
X-280/23=-10
Multiply each term by 23
23X-280=-230
add 280 to both sides
23X=50
Divide both sides by 23
X=50/23
Let's plug in the values to confirm
x - 7y = -10
50/23-7(40/23)=-10 (50-280)/23=-230/23=-10
3x + 2y = 10 3(50)/23 +2(40/23)=10 150/23+80/23=230/23=10