5x^3-20x^2 -60x
x^2 +7x - 4x -28
2007-07-10 15:58:45 · 5 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
5x³-20x²-60x
First, factor 5x out of each term:
5x(x²-4x-12)
Then, factor the trinomial:
5x²(x-6)(x+2)
x²+7x-4x-28
First, group like terms (7x-4x):
x²+3x-28
Then factor:
(x+7)(x-4)
Remember you're looking for numbers that multiply to give you the last term as well as combine to give you the middle term: (7)(-4)= -28; 7-4=3
2007-07-10 16:14:57 · answer #1 · answered by gm 2 · 0⤊ 0⤋
For the first one:
5x^3 - 20x^2 - 60x
x(5x^2 - 20x - 60)
5x(x^2 - 4x - 12)
5x(x + 6)(x - 2) and 5x(x - 6)(x - 2)
For the second one (providing that you didn't forget to put in anything):
x^2 + 7x - 4x - 28
x^2 + 3x - 28
(x + 7)(x - 4) and (x - 7)(x + 4)
2007-07-10 16:12:06 · answer #2 · answered by Riven Liether 5 · 0⤊ 0⤋
5x^3-20x^2 -60x factor out 5x
5x(x²-4x-12)
5x(x-6)(x+2)
x^2 +7x - 4x -28 combine like terms
x²+3x-28
(x+7)(x-4)
2007-07-10 16:07:07 · answer #3 · answered by yupchagee 7 · 0⤊ 0⤋
5x^3-20x^2 -60x =
5x ( x^2- 4x -12) =
5x (x -6) (x + 2)
x^2 +7x - 4x -28=
x^2 +3x -28=
(x + 7) (x -4 )
2007-07-10 16:05:32 · answer #4 · answered by ignoramus 7 · 0⤊ 0⤋
5x^3 - 20x^2 - 60x =
5x(x^2 - 4x - 12) =
5x(x + 2)(x - 6)
x^2 +7x - 4x -28 =
(x - 4)(x + 7)
2007-07-10 16:11:31 · answer #5 · answered by Helmut 7 · 0⤊ 1⤋