+0  
 
0
195
1
avatar+7 

How do you factor the trinomial 2p^2-3p-54

Annabelle  Apr 1, 2015

Best Answer 

 #1
avatar+91510 
+10

$$2p^2-3p-54$$

 

first I would look for 2 numbers that mult to 2*-54=-108

since it mult to a negative one must be positive and the other one negative.

BUT they also have to add to -3    So the 'bigger' one will be neg and they must be close together. (3 apart.)

Now i am just going to 'play' with the factors of 108.

108=4*27 = 4*3*3*3=9*12      BINGO

-12 and +9

NOW

I will split -3p up into  -12p+9p

 

$$\\2p^2-3p-54\\
=2p^2-12p+9p-54\\
$now factorise in pairs$\\
=2p(p-6)+9(p-6)\\
=(2p+9)(p-6)\\$$

 

And that is it :)

Melody  Apr 1, 2015
Sort: 

1+0 Answers

 #1
avatar+91510 
+10
Best Answer

$$2p^2-3p-54$$

 

first I would look for 2 numbers that mult to 2*-54=-108

since it mult to a negative one must be positive and the other one negative.

BUT they also have to add to -3    So the 'bigger' one will be neg and they must be close together. (3 apart.)

Now i am just going to 'play' with the factors of 108.

108=4*27 = 4*3*3*3=9*12      BINGO

-12 and +9

NOW

I will split -3p up into  -12p+9p

 

$$\\2p^2-3p-54\\
=2p^2-12p+9p-54\\
$now factorise in pairs$\\
=2p(p-6)+9(p-6)\\
=(2p+9)(p-6)\\$$

 

And that is it :)

Melody  Apr 1, 2015

18 Online Users

avatar
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