Safe-Keeper wrote:2x(3x+5y)-5y(1y+2x)+60
=(Ask Internet to do my homework for me)
=6x+10y-5y^2-10xy+60

Thats wrong. (on second note how come you got the EXACT same wrong answer as Yultmese?)
ORIGINAL PROBLEM
0. 2x(3x+5y)-5y(1y+2x)+60=0
MULTIPLING gives us
1. (6x^2+10xy)+(-5y^2-10xy)+60=0
SIMPLIFY (since 10xy and -10xy have the same variables they are LIKE TERMS allowing for them to be combined. As a result you get 10xy-10xy=0 ) gives us
2. 6x^2-5y^2+60=0
REARANGE TO y=M(x)+b or Cartesian Form (optional)
3. 6x^2+60= -5y^2
REDUCE the value of -5y^2 to just -y^2 (divide both sides by -5)
4.
6x^2+60=-y^2
----5
REDUCE the value of -y^2 to just y (take the SQUARE ROOT of both sides; in effect you square -y which produces a positve number allowing you to take a positive square root resulting in a postive y)
5.
SquareRoot(6x^2+60)=y
-------------(5)
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TY gives an almost accurate possiblity for the values of y and x (off by 1.25 if you plug in the numbers and chug with the original and off by .02
if you plug in the numbers with my simplification) however since this problem has two variables it by nature has an infinte number of possibilites unless bounded by another equation or some obscure rule you forgot to mention.
In essence we just simplified an X-Y coordinate FUNCTION [f(x)=y], which would result in a graph like a parabola.
Hope this helps SD