anonymous 3 years ago t^2+6t-7. Is their a 2 numbers that equael product -7 and sum 6. Is it just me or thats not possible?

1. KingGeorge

That's just you :) There are indeed two numbers that multiply to be -7, and add to be 6. Think about it a bit and I'm sure you'll get it.

2. anonymous

Well the equation is set up as (a+1) (a-7) thats what I got. but 1-7=-6 so that doesnt work.

3. anonymous

remember that - and + in front of the numbers

4. anonymous

Wrong way around mate

5. KingGeorge

That's very close.

6. anonymous

ok got it switched them. Now it works.

7. KingGeorge

Excellent!

8. anonymous

Thanks lol I cant believe i cudnt figure tthat out

9. KingGeorge

No problem. We've all had something obvious pass us by before :P

10. anonymous

would the solution set be written as (a+7) (a-1) or just {7,-1}

11. anonymous

are you factorizing? normally it wuold be written as full.

12. UnkleRhaukus

you could always use the quadratic formula $t=\frac{-b\pm\sqrt{b^2-4ac}}{2a}$

13. anonymous

(a+7)(a-1) that is.... you will need to use the full factors to use in equations.

14. KingGeorge

The solution set would be {-7,1}. Note that you have -7 and +1 because if $$a+7=0$$, then $$a=-7$$. Similarly, $$a-1=0\implies a=1$$.

15. anonymous

@Ben103 sorry the questions look like what I'm doing at school at the moment which is factorizing :( I could be wrong

16. anonymous

@KingGeorge knows more than me i'm sure! lol I'm only doing high school maths

17. KingGeorge

As another tip, if you're asked for a solution SET, your final answer should look like {_,_,_,...,_}. I.e., you have a list of things in the curly brackets.

18. anonymous

Ok thanks I understand it now. :)

19. KingGeorge

You're welcome.