SOLUTION: I am having trouble finding the intersection of Y=3/2X+4 and Y=-6+2x Thanks Julian

Algebra ->  Linear-equations -> SOLUTION: I am having trouble finding the intersection of Y=3/2X+4 and Y=-6+2x Thanks Julian      Log On


   

Question 73146: I am having trouble finding the intersection of Y=3/2X+4 and Y=-6+2x
Thanks Julian
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Set the two equations equal to each other. Since they both equal y, they both equal each other. For instance if we have y=x and y=5, then x=5 since we can substitute 5 into y.
Substitute y=highlight%28-6%2B2x%29 into highlight%28y%29=%283%2F2%29x%2B4
highlight%28-6%2B2x%29=%283%2F2%29x%2B4Now we have everything in terms of x. Solve for x.
2x=%283%2F2%29x%2B4%2B6Add 6 to both sides
2x-%283%2F2%29x=10Subtract 3/2x from both sides
%281%2F2%29x=10Multiply both sides by 2
x=20
Substitute this back into y=%283%2F2%29x%2B4
y=%283%2F2%29%2820%29%2B4
y=3%2A10%2B4
y=34
Check:
y=-6%2B2xUse this first
34=-6%2B2%2A20
34=-6%2B40
34=34Works
34=%283%2F2%29x%2B4Next use this equation to check
34=%283%2F2%29%2820%29%2B4
34=3%2A10%2B4
34=34Works


So the intersection is (20,34)