## angelwings996 2 years ago What is the number of real solutions? -11x^2 = x + 11

1. dumbcow

first set equal to zero second find discriminate (b^2 -4ac) third, if discriminate >0 : 2 real solutions if discriminate =0: 1 real solution if discriminate <0 : no real solutions

2. angelwings996

would the equation be -11x^2 - x - 11 = 0 ?

3. dumbcow

yes or you can get rid of the neg --> 11x^2 +x+11 = 0

4. angelwings996

Okay, now what would I do?

5. dumbcow

find Discriminant http://en.wikipedia.org/wiki/Discriminant

6. hartnn

7. angelwings996

don't I already have a, b, and c so would I just substitute them into b^2 - 4ac ?

8. hartnn

what u got, a=..? b=...?c=..?

9. angelwings996

doesn't a = 11, b = 1, and c = 11 ?

10. hartnn

thats correct, now as @dumbcow said, u just need to find whether b^2-4ac is positive or negative...

11. angelwings996

so if I plug it in would it be like this .... \[1 ^{2} - 4(11)(11)\]

12. hartnn

yes, go on.

13. angelwings996

okay so \[1^{2} = 1 and -4(11) = -44(11) = -484\] Then you would subtract -484 from 1 which gives you -483, right ?

14. hartnn

yes, so how many real solutions ?

15. angelwings996

since -483 is less than 0 would it be no real solutions?

16. hartnn

absolutely correct :)

17. angelwings996

Okay thank you so much for both of your helps!

18. hartnn

welcome ^_^