SOLUTION: Question: What is the x-coordinate in the solution of the system of equations 4x-5y=-3, 3x+y=-7? thanks for your help.

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Question 202234: Question: What is the x-coordinate in the solution of the system of equations 4x-5y=-3, 3x+y=-7? thanks for your help.
Answer by jojo14344(1513) About Me  (Show Source):
You can put this solution on YOUR website!


Given, system%284x-5y=-3%28red%28EQN1%29%29%2C3x%2By=-7%28red%28EQN2%29%29%29

In red%28EQN1%29, let us isolate "y":
4x-5y=-3
4x%2B3=5y ---> %284x%2B3%29%2F5=cross%285%29y%2Fcross%285%29
y=%284%2F5%29x%2B3%2F5, red%28EQN3%29, substitute in red%28EQN2%29:

3x%2Bhighlight%28%284%2F5%29x%2B3%2F5%29=-7
3x%2B%284%2F5%29x=-7-3%2F5
%2815x%2B4x%29%2F5=%28-35-3%29%2F5
19x%2F5=-38%2F5 , cross multiply
19x=%28cross%285%29%29%28-38%2Fcross%285%29%29
cross%2819%29x%2Fcross%2819%29=cross%28-38%292%2Fcross%2819%29
red%28x=-2%29, Answer

If we look the graph,
---> red%284x-5y=-3%28EQN1%29%29;green%283x%2By=-7%28EQN2%29%29; See x coordinate of Point of Intersection = -2

Thank you,
Jojo