Question

use the quadratic formula to solve x^2+x-1=0

Answer 1

Ok, try to plug in here:
\[\frac{-b\pm \sqrt{b^2-4ac}}{2a}\]
where a=1,b=1 and c=-1

Answer 2

hey i just did one for you, now try yourself !!!!!

Answer 3

very famous number you get too!

Answer 4

The equation is given in standard form,
\[ax ^{2}+bx+c = 0\]

the quadratic equation is what watchmath gave you. Now all you have to do is plug in a, b, and c to find what x is equal to

Answer 5

the quadratic formula is
-b +/-sqrt ( b^2-4ac)/2a
substitute the value of of - b which would be -( 1)
substitute the value of c which is -1
substitute the value of a which is 1
-(1) +- sqrt( (1)^- 4(1)(-1) )\2(1)

Answer 6

so what is the answer

Answer 7

a = 1
b = 1
c = -1 plug in to
\[x=\frac{-b\pm\sqrt{b^2-4ac}}{2a}\]

Answer 8

i got -1+- square root of -3

Answer 9

made a mistake with the - sign in
\[b^2-4ac\]

Answer 10

it is
\[(-1)^2-4\times 1\times -1\]

Answer 11

\[=1+4=5\]

Answer 12

so answer is
\[\frac{-1\pm\sqrt{5}}{2}\]

Answer 13

ok but i have to have two answers in fractions it wont accept it like that