SOLUTION: -4x-15=5y 2y=11-5x

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Question 176116: -4x-15=5y
2y=11-5x
Answer by jojo14344(1513) About Me  (Show Source):
You can put this solution on YOUR website!

-4x-15=5y, EQN 1
2y=11-5x, EQN 2
In EQN 1 we get,
y=%28-4x-15%29%2F5=%28-4%2F5%29x-%2815%2F5%29
y=%28-4%2F5%29x-3, EQN 3------> subst. in EQN 2:
2%28%28-4%2F5%29x-3%29=11-5x
%28-8%2F5%29x-6=11-5x
%28-8%2F5%29x%2B5x=11%2B6
%28-8x%2B25x%29%2F5=17, cross multiply
17x=85---->cross%2817%29x%2Fcross%2817%29=cross%2885%295%2Fcross%2817%29
highlight%28x=5%29, subst. in EQN 2:
2y=11-5x--->y=%2811-5x%29%2F2=%28-5%2F2%29x%2B%2811%2F2%29
y=%28-5%2F2%29%285%29%2B%2811%2F2%29=%28-25%2F2%29%2B%2811%2F2%29=-14%2F2
highlight%28y=-7%29
See graph:
--->POINT of intersection (5,-7); RED,>>> EQN 1, GREEN,>>> EQN 2
Thank you,
Jojo