Factor this trinomial using the ac method.
2007-08-01 18:25:10 · 8 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
First you must write 15x^2 - 7x -2 as a polynomial with 4 terms
so split the middle term 7x into two and write it as a sum
15x^2 -8x +x -2
now you can factor by regrouping
(15x^2-8x) +(x-2)
now factor
x(15x-8)+ 1(x-2) = 0
2007-08-01 18:31:25 · answer #1 · answered by NKS 2 · 2⤊ 1⤋
15x^2 - 7x -2
= 15x^2 - 10x + 3x - 2
= 5x(3x-2) + (3x - 2)
= (5x+1)(3x-2)
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How to split the middle term?
Ideas: Factor 15(-2)x^2, the product of the leading term and the constant term, into -10x and 3x such that -10x + 3x = -7x, the linear term.
2007-08-02 01:29:31 · answer #2 · answered by sahsjing 7 · 0⤊ 1⤋
15x^2 - 7x - 2
= (5x + 1) (3x - 2)
2007-08-02 01:29:53 · answer #3 · answered by vlee1415 5 · 0⤊ 1⤋
15x^2 - 7x - 2
( 5x +1) (3x - 2 )
2007-08-02 02:03:58 · answer #4 · answered by CPUcate 6 · 0⤊ 1⤋
(5x + 1)(3x - 2)
Check
5x(3x - 2) + 1 (3x - 2)
15x² - 10x + 3x - 2
15x² - 7x - 2 (as required)
2007-08-02 05:37:40 · answer #5 · answered by Como 7 · 1⤊ 1⤋
15x^2 - 7x -2
= 15x^2 - 10x +3x-2
= (15x^2 - 10x)+(3x-2)
= 5x(3x-2))+ 1.(3x-2)
= (5x+1)(3x-2)
2007-08-02 01:30:45 · answer #6 · answered by Beurself 2 · 0⤊ 1⤋
(3x-2)(5x+1)
2007-08-02 01:29:47 · answer #7 · answered by 037 G 6 · 0⤊ 1⤋
c'mon. It's one thing to ask for how to approach a problem; another to ask for someone to just solve it for you.
2007-08-02 01:27:40 · answer #8 · answered by jkdeep6 3 · 0⤊ 1⤋