+0  
 
0
104
3
avatar

1) 6x^2 + 2xy - 15x - 5y

 

2) 2x^2 + 7x + 5

Guest Jul 19, 2017
Sort: 

3+0 Answers

 #1
avatar+76821 
+2

 

1) 6x^2 + 2xy - 15x - 5y

 

factor by grouping

 

2x (3x + y ) - 5 (3x + y)        (3x + y)   is common to both terms

 

(3x + y)   (2x - 5 )

 

 

2) 2x^2 + 7x + 5    we're looking for two terms that multiply to 2 for the first term and to 5 for the last term......trial and error produces

 

(2x + 5) (x + 1)

 

 

cool cool cool

 

 

cool cool cool

CPhill  Jul 19, 2017
 #2
avatar
0

wait, how did you get your last answer for question 2? :)

Guest Jul 19, 2017
 #3
avatar+4694 
+1

Here's another way to do that one....

 

2x2 + 7x + 5

 

Multiply the  2  and the  5  together to get  10  .

What two numbers multiply to  10  and add to  7  ? →   +2   and   +5

So, we can split the middle term like this:

 

2x2 + 2x + 5x + 5              Notice here how if we combined like terms, we'd get  7x  again.

                                          Factor  2x  out of the first two terms.

2x(x + 1) + 5x + 5

                                          Factor  5  out of the last two terms.

2x(x + 1) + 5(x + 1)

                                          Factor  (x + 1)  out of both remaining terms.

(x + 1)(2x + 5)

hectictar  Jul 19, 2017

10 Online Users

avatar
avatar
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