Question

what is the sum of the roots of the equation 2x^2+6x-7=0

Answer 1

b/2a?

Answer 2

think about the quadratic, one side is +sqrt(b^2 - 4ac), other side is minus

added together you get 1, leaving -b/2a

Answer 3

no, -b/a

Answer 4

forgot to add the 2 -b's

Answer 5

First, 2x^2 means 2*?*2
Next, 6x-7 means 6*?-7
Last, once you find whats missing add both sums then it will give you 0.

http://www.virtualnerd.com/ Search your topic on this website. The lady explains step by step in each process.

Answer 6

If you copy what she does on paper you will figure out what the missing numbers are

Answer 7

k(x-a)(x-b) => k x^2-k(a+b)x+kab.
k=2
-k(a+b)=6
a+b=-3
sum of roots=-3

Answer 8

http://www.artofproblemsolving.com/Wiki/index.php/Vieta's_Formulas

Answer 9

I think my way is easier :P