plz help me break down this quadratic equation?

0 ⤊

plz help me break down this quadratic equation?

15x^2+4x-35=0

i know i have to factor it out...
(15x ____ ) ( x ____ )
what goes in the blanks?
and why? and is there a trick to remember how to do it quickly?
thanks so much!

2007-10-02 12:11:18 · 3 answers · asked by Angelica 1 in Science & Mathematics ➔ Mathematics

3 answers

35*15 = 7*5*3*5 = 25*21

25-21 = 4

15x^2 + 25x - 21x - 35

5x(3x+5) - 7(3x + 15)

(3x+5)(5x-7)

(3x+5)(5x-7)

2007-10-02 12:19:11 · answer #1 · answered by mohanrao d 7 · 0⤊ 0⤋

15x^2+4x-35=0
= (5x-7)(3x+5)

Do not assume that 15 and 1 are the only factors of 15.

2007-10-02 19:18:25 · answer #2 · answered by ironduke8159 7 · 0⤊ 0⤋

15x^2 + 4x - 35 = 0
(3x +5) (5x-7 ) = 0

2007-10-02 19:16:44 · answer #3 · answered by CPUcate 6 · 0⤊ 0⤋