2007-11-24 17:29:40 · 10 answers · asked by nabs l 1 in Science & Mathematics ➔ Mathematics
(2x - 1) (x + 4)
Check
2x² + 8x - x - 4
2x² + 7x - 4 (as required)
2007-11-25 00:35:29 · answer #1 · answered by Como 7 · 3⤊ 1⤋
2x^2 + 7x - 4
Ok, we know that the only possibility to get 2x^2 is by multiplying 2x and x. So, let's put that down first.
(2x ___ )(x ___ )
Now, let's look at the 4. Ignore whether it is positive or negative. Let's consider the possible factors of 4. It's either 4 and 1 or 2 and 2. We should try 4 and 1. But, the question is, which space should we slot it in? I know that the 4 is definetly not going to be placed next to the 2x because if I did that, I would have a GCF. But, I did not have a GCF to start with in the first place, so therefore the 4 will go in the space next to the "x." And the 1 will go next to the "2x"
(2x 1 )(x 4)
The final step is to decide what signs there will be. The only way to get -4 is by doing -1 x 4 or 1 x -4. So, after you test it out you will see that the answer will be:
(2x - 1 )(x + 4)
2007-11-25 01:43:15 · answer #2 · answered by Anonymous · 0⤊ 2⤋
S=7
P=2*-4=-8
nos:=8 , -1
2x^2+7x-4
=2x^2+8x-x-4
=2x(x+4)-1(x+4)
=(2x-1)(x+4)
2007-11-25 01:41:58 · answer #3 · answered by sonu_may 1 · 0⤊ 1⤋
2x^2+7x-4
= (2x - 1)(x + 4)
x=1/2 or x=-4
2007-11-25 01:33:47 · answer #4 · answered by Anonymous · 0⤊ 1⤋
2x^2 +8x -x -4=0
2x(x +4) -1(x+4)=0. (2x-1) (x+4)=0.
2x-1=0. x=1/2. x+4=0. x= -4.
Ans. x=1/2. x= -4.
2007-11-25 07:42:58 · answer #5 · answered by Sasi Kumar 4 · 0⤊ 1⤋
(2x - 1) (x+4)
2007-11-25 01:34:09 · answer #6 · answered by sayamiam 6 · 0⤊ 0⤋
(2x-1)(x+4)
2007-11-25 01:33:36 · answer #7 · answered by Jack B. 3 · 1⤊ 0⤋
(2x-1)(x+4)
2007-11-25 02:41:39 · answer #8 · answered by Anonymous · 0⤊ 1⤋
(2x-1)(x+4)=0
x=1/2 or x=-4
2007-11-25 01:33:39 · answer #9 · answered by golffan137 3 · 1⤊ 1⤋
(2x-1)(x+4)
2007-11-25 01:32:25 · answer #10 · answered by Briana L 4 · 1⤊ 1⤋