SOLUTION: How to I find the point of intersection between y=-3.3/23.7*x+437/79 and y = 9.75/-10*x+8.675? Can you please use the elimination or substitution method. Thanks!

Algebra ->  Coordinate Systems and Linear Equations  -> Lessons -> SOLUTION: How to I find the point of intersection between y=-3.3/23.7*x+437/79 and y = 9.75/-10*x+8.675? Can you please use the elimination or substitution method. Thanks!      Log On


   

Question 967172: How to I find the point of intersection between y=-3.3/23.7*x+437/79 and y = 9.75/-10*x+8.675? Can you please use the elimination or substitution method. Thanks!
Answer by macston(5194) About Me  (Show Source):
You can put this solution on YOUR website!
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y=%28-3.3%2F23.7%29x%2B437%2F79
y+=%289.75%2F-10%29x%2B8.675 Use first equation to substitute for y.
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%28-3.3%2F23.7%29x%2B%28437%2F79%29=%289.75%2F-10%29x%2B8.675 Convert fractions to decimals.
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0.139x%2B5.532=-0.975x%2B8.675 Add 0.975x to each side.
1.114x%2B5.532=8.675 Subtract 5.532 from each side.
1.114x=3.143 Divide each side by 1.114.
x=2.821 Use this in first equation and solve for y.
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y=%28-3.3%2F23.7%29x%2B437%2F79
y=%28-3.3%2F23.7%29%282.821%29%2B437%2F79
y=%280.139%29%282.821%29%2B%285.532%29
y=%280.392%29%2B%285.532%29
y=5.924
ANSWER: The solution to the system is (2.821,5.924)
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CHECK:
Use second equation to check.
y+=%289.75%2F-10%29x%2B8.675 Plug in values.
5.924=%289.75%2F-10%29%282.821%29%2B8.675
5.924=%28-0.975%29%282.821%29%2B8.675
5.924=%28-2.750%29%2B8.675
5.924=5.924