+0

# Factoring

0
96
3
+648

How do I factor this equation?

$$3x^2+5x+2$$

I tried, but the answer I came up with didn't match with my teacher's answers, so I want a second opinion.

AdamTaurus  Sep 26, 2017
Sort:

#1
+91229
+2

$$3x^2+5x+2\\$$

First you need to find two numbers that multiply to give 3*2=6

Obviously they need to be of the same sign (positive or negative)

They also need to add to 5.    Since 5 is positive both numbers must be positive.

2 and 3 work

2+3=5

2*3=6

so now you need to write 5x as 3x+2x

$$3x^2+5x+2\\ =3x^2+3x+2x+2\\ =3x^2+3x\quad+\quad2x+2\\ \text{Now factor in pairs}\\ =3x(x+1)\quad + \quad 2(x+1)\\ =(3x+2)(x+1)$$

Melody  Sep 26, 2017
#2
+648
+2

Ohhhh. Okay. I see what I did wrong. I was only thinking about adding to 5 so I tried -1 and 6. Thanks!

AdamTaurus  Sep 26, 2017
#3
+91229
+1

I am glad I could help.

You can expand your final answer to see if it is correct or not.

It is always good to check answers :)

Melody  Sep 26, 2017

### 10 Online Users

We use cookies to personalise content and ads, to provide social media features and to analyse our traffic. We also share information about your use of our site with our social media, advertising and analytics partners.  See details