SOLUTION: Solve this system using the substitution method. -2x - y = -7 x + 7y = 10 Solve using the substitution method and be sure to show all of your work.

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Question 1203927: Solve this system using the substitution method. -2x - y = -7 x + 7y = 10 Solve using the substitution method and be sure to show all of your work.
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!
-2x+-+y+=+-7......eq.1
x+%2B+7y+=+10....eq.2
____________________________
start with
-2x+-+y+=+-7......eq.1, solve for y

y=-2x%2B7++

substitute in eq.2
x+%2B+7%28-2x%2B7%29+=+10....eq.2, solve for x

x+-14x%2B49+=+10
+-13x%2B49+=+10
+-10%2B49+=+13x
+39+=+13x
+x=39%2F13
+x=3

go to

y=-2x%2B7++, substitute x
y=-2%2A3%2B7++
y=-6%2B7++
y=1+


+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2C+-2x%2B7+%2C+-x%2F7%2B10%2F7%29+