I need to factor this polynominal if factoring is possible, I need to show the results of factoring out of GCF before taking the resulting polynomial and factoring it again, could you please help and put it into englich for me thanks a bunch. 8x^2 + 6x -5
2007-05-22 03:57:46 · 3 answers · asked by ambi565 2 in Science & Mathematics ➔ Mathematics
8x² + 6x + 5 = 0
The middle term is + 6x
find the sum of the middle term
Multiply the first term 8 times the last term 5 equals 40 and factor
The factors of 40
1 x 40
2 x 20
4 x 10 . . . <=. .Use these factors
8 x 5
- 4 and + 10 satisfy the sum of the middle term
insert - 4x and + 10x into the equation'
8x² + 6x + 5 = 0
8x² - 4x + 10x - 5 = 0
4x(2x - 1) + 5(2x - 1) = 0
(4x + 5)(2x - 1) = 0
- - - - - - - - - - -s-
2007-05-22 05:33:25 · answer #1 · answered by SAMUEL D 7 · 0⤊ 0⤋
I am sorry but I don't understand the question.
This is a standard trinomial and if it factorises then it will be of the shape (ax + b)(cx + d) where ac = 8 and bd = -5
Guess that it goes (4x + ...)(2x + ...)
Factors of -5 are easier, just 1, -5 or -1 and 5
Guess that it goes (4x + 5)(2x - 1)
Multiply out and you get 8x² + 6x - 5 which is what you wanted.
You just have to try all the possible pairs until you find the right one . I was lucky to get it first time.
2007-05-22 11:15:18 · answer #2 · answered by fred 5 · 0⤊ 0⤋
x= 1/2 or x= -5/4
8x^2+6x-5= (4x+5)(2x-1)
4x+5=0 or 2x-1=0
4x= -5 or 2x= 1
therefore, x= -5/4 or 1/2
get it?
2007-05-22 11:23:15 · answer #3 · answered by Anonymous · 0⤊ 0⤋