Ok, basically if you want to find when both equations are equal just make them equal to each other. 0.925x^2 - 4x + 20 = -1.125x^2 + 6x + 40.
From there use algebraic steps to find out what x is ( the break - even point ).
0.925x^2 - 4x + 20 = -1.125x^2 + 6x + 40
0.855625x - 4x + 20 = 1.265625x + 6x + 40
-0.41x - 4x + 20 = 6x + 40
-4.41x + 20 = 6x + 40
20 = 10.41x + 40
-20 = 10.41x
-1.92122958694 = x
Rounded to the nearest tenth it's -1.9 = x.
Tell me if I got something wrong :)