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3x^2 +2x-1=0

Guest Nov 21, 2014

Best Answer 

 #1
avatar+92191 
+5

3x^2 +2x-1=0

 

I am looking for 2 numbers that mult to 3*-1=-3   and add to +2

I see that the numbers are  -3 and +1

so now I will split 2x into  -3x+1x

 

$$\\3x^2 +2x-1=0\\
3x^2-3x +1x-1=0\\
3x(x-1) +1(x-1)\\
(3x+1)(x-1)=0$$

 

3x+1=0   or    x-1=0

3x=-1      or     x=1

x= -1/3    or     x=1

Melody  Nov 21, 2014
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1+0 Answers

 #1
avatar+92191 
+5
Best Answer

3x^2 +2x-1=0

 

I am looking for 2 numbers that mult to 3*-1=-3   and add to +2

I see that the numbers are  -3 and +1

so now I will split 2x into  -3x+1x

 

$$\\3x^2 +2x-1=0\\
3x^2-3x +1x-1=0\\
3x(x-1) +1(x-1)\\
(3x+1)(x-1)=0$$

 

3x+1=0   or    x-1=0

3x=-1      or     x=1

x= -1/3    or     x=1

Melody  Nov 21, 2014

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