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505-555 Level|   Algebra|      
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malkov
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3x^2 + 2x - 8 = 13 May 2012, 22:53
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B
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15% (low)

Question Stats:

77% (01:07) correct 23% (01:29) wrong based on 457 sessions

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3x^2 + 2x - 8 =

A. (3x-4)(x-2)
B. (3x-4)(x+2)
C. (3x-4)(x-2)
D. (3x-2)(x+4)
E. none of above
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B
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GyanOne
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3x^2 + 2x - 8 = 13 May 2012, 23:15
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3x^2 + 2x - 8
= 3x^2 + 6x - 4x - 8
= 3x (x + 2) - 4 (x+2)
= (3x-4) (x+2)

Option B
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3x^2 + 2x - 8 = 14 May 2012, 00:09
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malkov
3x^2 + 2x - 8 =

A. (3x-4)(x-2)
B. (3x-4)(x+2)
C. (3x-4)(x-2)
D. (3x-2)(x+4)
E. none of above
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Solving and Factoring Quadratics:
https://www.purplemath.com/modules/solvquad.htm
https://www.purplemath.com/modules/factquad.htm

Hope it helps.
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3x^2 + 2x - 8 = 14 May 2012, 01:05
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3x^2 + 2x - 8

X1*X2=-8/3
X1+X2=-2/3

Only option B satisfies these parameters
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3x^2 + 2x - 8 = 21 Jan 2016, 07:11
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1. just open the brackets. A is out, B is in. 30 secs.

2. factoring box

a. 3x^2 + 2x - 8 -> mulptiply a and c = 3*-8 = -24
b. factors of -24 that add up to b (i.e. 2) are 6 and -4 (note that the larger factor should be positive because b is positive, one of the factors is negative)
c. arrange the box as below and find common factors in the 2 vertical and 2 horizontal lines. form equation. of (3x-4)(x+2)
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box.jpg [ 7.22 KiB | Viewed 9603 times ]

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3x^2 + 2x - 8 = 04 Apr 2019, 06:22
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I used quadratic equation in solving this
3x^2+2x-8=
X=-b+/- sqrt b^2-4ac/2a
Where a =3, b=2, And c=-8
X=-2+/-sqrt 2^2-4(3)(-8)/2(3)
X=-2+/-sqrt 4+96/6
X=-2+/-sqrt100/6=-2+/-10/6
X=-2+10/6 or X=-2-10/6
X=8/6=4/3 or X=-12/6=-2
Therefore X=4/3 or -2
X=4/3= 3x=4, 3x-4=0
X=-2, X+2=0
So we have 3x-4=0 or x+2=0
Final answer (3x-4)(x+2)
Answer is B

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3x^2 + 2x - 8 = 04 Apr 2019, 06:27
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I used quadratic equation in solving this
3x^2+2x-8=
X=-b+/- sqrt b^2-4ac/2a
Where a =3, b=2, And c=-8
X=-2+/-sqrt 2^2-4(3)(-8)/2(3)
X=-2+/-sqrt 4+96/6
X=-2+/-sqrt100/6=-2+/-10/6
X=-2+10/6 or X=-2-10/6
X=8/6=4/3 or X=-12/6=-2
Therefore X=4/3 or -2
X=4/3= 3x=4, 3x-4=0
X=-2, X+2=0
So we have 3x-4=0 or x+2=0
Final answer (3x-4)(x+2)
Answer is B

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3x^2 + 2x - 8 = 07 Apr 2019, 18:43
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malkov
3x^2 + 2x - 8 =

A. (3x-4)(x-2)
B. (3x-4)(x+2)
C. (3x-4)(x-2)
D. (3x-2)(x+4)
E. none of above
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Factoring the given quadratic expression, we have:

(3x - 4)(x + 2)

Answer: B
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3x^2 + 2x - 8 = 17 Sep 2024, 09:25
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3x^2+2x-8=?
3x^2+6x-4x-8
3x(x+2)-4(x+2)
(3x-4)(x+2)

Answer: B

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