Solve using elimination
the equations below model the numbers y of two portable music players sold x days after both players were introduced. on what day(s) did the company sell the same number of each player? how many players of each type were sold?
player a : y=48x+20
player b : y=-x^2+200x+20

so far i've subtracted b from a, giving me :
0=x^2-152x
was this the right thing to do? i don't know how to solve it from here, since it cannot be or does this mean theres no solution?
you!