How do I factor these prob?

Question

1. 4x^2 +7x-2

And how do I solve this by factoring?
2. 2x^2-9x-5=0

Answer 1

It is here:

http://www.themathpage.com/alg/factoring-trinomials.htm
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Answer 2

The equation is in the form ax^2+bx+c where:

a= 2
b= -9
c= -5

Use a to multiply c, that is ac = -10.


f you can find two numbers that multiply to give ac and also add to give b, then you can factorise. If you can't 2 such numbers you cannot factorise.

In this case the numbers are +1 and -10.

We use these 2 numbers to rewrite the b term in the original equation. Here goes:

2x^2-9x-5=0, -10+1 =-9, so we can rewrite as:
2x^2-10x+x-5 =0 (it doesn't matter which number comes first)
(2x^2-10x)+(x-5) =0 (Dividing into pairs of bracketed terms)
2x(x-5)+1(x-5) =0 (Factorising each bracketed term)

(x-5)(2x+1) =0 (Second factorisation)

Hence: x= 5 or x=-1/2, Use these to test the original equation

Answer 3

selection a million: 4x^2 factors out to become this: (4x _ _)(x _ _) the blanks stand for the sign and the selection. next you ingredient the -2, which should not be that no longer basic. factors are -a million and a couple of. so plainly like this now: (4x - a million)(x + 2) to earnings the respond: 4x * 2 = 8x -a million * x = -1x 8x + (-1x) = 7x so the respond is (4x - a million)(x + 2) selection 2: this one is exceptionally very like the single on the best, yet you may remedy on the top. so, to commence you ingredient 2x^2 which turns into this: (2x _ _)(x _ _) next, you ingredient -5. its factors are a million and -5. so now the type appears like this (2x+a million)(x-5) now you examine the factoring. 2x * -5 = -10x a million * x = 1x -10x + 1x = -9x so now all of us understand that the pair (2x + a million)(x - 5) is genuine. now you remedy. to remedy, you purely discover the values of x. shall we start up with (2x + a million) first ingredient you do is purely upload =0 on the top of it, then remedy from there. 2x + a million = 0 subtract a million to the two factors. 2x = - a million divide by making use of two on the two factors. x= -a million/2 next, you remedy for (x - 5) which does no longer take a rocket scientist to verify. x - 5 = 0 upload 5 to the two factors. x = 5 there. so the answer to the 2nd question could be: x= -a million/2, 5. i'm hoping that helped and wasn't too puzzling. [:

Answer 4

1. (4x-1)(x+2)

4*2 is 8 which is also 8*1. and 7 can be written as 8-1. so, see that u have 4,2,8,1 in the picture.

2. 2x^2-9x-5=0 can be written as (2x+1)(x-5)=0.
That implies x= -1/2 or x= 5.

Answer 5

Question 1
(4x - 1) (x + 2)

Question 2
(2x + 1) (x - 5) = 0
x = - 1 / 2 , x = 5

Answer 6

1. 4x^2 +7x-2 = (4x-1)(x+2)
2. 2x^2-9x-5 = (2x+1)(x-5) = 0,
x = -1/2 or 5
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Ideas: Factor the product of the leading coefficient and the constant term into two factors such that the sum of the two factors equals to the coefficient of the linear term.

Answer 7

first 4x^2=7x-2will be solved as follows
(4x-1)(x+2)
so x=1/4 or x=-2
second2x^2-9x-5 will b solved as follows
(2x+1)(x-5)
so x=5 or x=-1/2
i am completly sure

Answer 8

When you have a coefficient # 1 with the x^2 term, it becomes somewhat harder.

The general approach is to split the equation so:
Ax (Bx + C) + D (Bx+C) =0 and determine the constants A,B,C and D.

1. By inspection (4x-1)(x+2)
2. By inspection (2x+1)(x-5)

Answer 9

1. (4x - 1) (x + 2)

2.(2x + 1) (x - 5)
(2x + 1) = 0 (x - 5) = 0
-1 -1 +5 +5
2x = -1 x = 5
--- ----
2 2

x= -1/2

Answer 10

4x^2 +7x-2
=(x+2)(4x-1)

2x^2-9x-5=0
(x-5)(2x+1)=0
x=5 or x=-0.5

Answer 11

4x² + 7x - 2 = 0

4x² + 8x - 1x - 2 = 0

2x(x + 2) - 1(x + 2) = 0

(2x - 1)Ix + 2) = 0

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2x² - 9x - 5 = 0

2x² - 10x + 1x - 5 = 0

2x(x - 5) + 1( x - 5) = 0

(2x + 1)(x - 2) = 0

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