SOLUTION: I am working on solving systems by substitution and elimination. An example problem is {-7x-y=-31 nxt line -7x=23 I have x=-23/7 y=-7(-23/7)+31=54. my question is how do I get the

Question 435214: I am working on solving systems by substitution and elimination. An example problem is {-7x-y=-31 nxt line -7x=23 I have x=-23/7 y=-7(-23/7)+31=54. my question is how do I get the 54???
Answer by ewatrrr(24785) (Show Source): You can put this solution on YOUR website!



Hi

-7x=23              |Yes, x = -23/7

-7x-y=-31 

-7*-23/7 - y = -31  |substituting for x

  23 - y = -31      |solving for y   Note: 

    54 = y 

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