## ikoreanx3 2 years ago Factor. 5x^2+5x-30

1. whpalmer4

5*-30 = -150. Can you think of two numbers which multiplied give you -150, and added give you 5?

2. ZeHanz

I would first factor out a 5: 5(x²+x-6). Now look for two numbers, with product 6 and sum 1 (because it is 1*x)

3. ikoreanx3

so would it be 5(x )(x ) ?

4. ZeHanz

Yes, and put the numbers that have sum 1 and produc -6 on the blanks...

5. ikoreanx3

Don't you have to find the mutiples of -30. . . that sum to 5

6. ZeHanz

You could also do it that way, but because I have factored out the 5, the other numbers can be smaller, so easier (imo)

7. ikoreanx3

I got confused with your method, I'm sorry.

8. ZeHanz

Can you find the numbers? Their sum is 1, their product = -6, because you have to factor x²+1x-6

9. ikoreanx3

i got 5(x-2)(x+3)

10. ZeHanz

Fine! That's all.

11. whpalmer4

Yes, factoring out the 5 does make it a little easier, and your factoring is correct. Good job!

12. ikoreanx3

Thank you, guys

13. whpalmer4

I like leaving the extra factors in so I get practice for the times when I can't factor them out :-)

14. whpalmer4

Just about everything is easier with practice, so practicing the really hard stuff narrows the gap between easy and hard...

15. ZeHanz

So you like torturing yourself... ;)

16. whpalmer4

In moderation :-)

17. ZeHanz

OK, carry on then!

18. ikoreanx3

o.o lol