x(x + 8)(x + 5)
It is: (x2 + 5x) (x + 8)
x3 + 13x2 + 42x = x(x + 6)(x + 7).
X3 + 13X2 + 40X factor out an X X(X2 + 13X + 40) factor the quadratic expression, what two factors of 40 add up to 13? X(X + 8)(X + 5) works the same if that is a negative in front of X3, just sign changes
x3 + 13x2 + 42x = x(x2 + 13x + 42) = x(x2 + 6x + 7x + 42) = x[x(x + 6) + 7(x + 6)] = x(x + 7)(x + 6)
x3+13x2=-22xadd 22x to both sides:x3+13x2+22x=0now factor:x(x2+13x+22)=0x(x+11)(x+2)=0x=0x+11=0x+2=0Therefore the solution to this equation is x=0, x=-11, x=-2
(x2 plus 40) (x minus 1)
x3 + 2x2 - 35x = x(x + 7)(x - 5)
x(x + 9)(x + 5)
x3 - 7x2 + 6x =x (x2 - 7x + 6) =x (x - 6) (x - 1)
x3 - 12x2 + 35x = x (x2 - 12x + 35) = x (x - 7) (x - 5)
34 · m2 · x3
2x3 - 7 + 5x - x3 + 3x - x3 = 8x - 7