(4 - x)*(2*x - 10)
(4 - x)*(2*x - 1*10)
1*(x - 4)*(x - 5)
(1*(x - 4))*(x - 5)
-2*(-5 + x)*(-4 + x)
(4.0 - x)*(-10.0 + 2.0*x)
2 -40 - 2*x + 18*x
-40 - 2*x^2 + 18*x
2*(-5 + x)*(4 - x)