SOLUTION: what are the coordinates of 5x+20y=100 and x+3y=15

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Question 1128391: what are the coordinates of 5x+20y=100 and x+3y=15
Answer by MathLover1(20855) About Me  (Show Source):
You can put this solution on YOUR website!

5x%2B20y=100 ...eq.1.....simplify, both sides divide by 5
x%2B3y=15.......eq.2
--------------------
x%2B4y=20 ...eq.1
x%2B3y=15.......eq.2
---------------------------subtract eq.2 from eq.1
x%2B4y-%28x%2B3y%29=20-15
x%2B4y-x-3y=5
y=5
go back to x%2B3y=15.......eq.2, substitute y value
x%2B3%2A5=15
x%2B15=15
x=15-15
x=0
=> intersection point of these two lines is at (0,5)