Question

what are the roots of the equation
−x2 − 2x + 8 = 0?
How do you solve this?

Answer 1

D=b^2-4ac=4-4*(-1)*8=36>0
x1=(-b+sqrD)/2a=2+6/-2=-4
x2=(-b-sqrD)/2a=(2-6)/-2=2

Answer 2

it takes a good eye, or a remembrance of the quadratic formula

Answer 3

it is \[-(x ^{2}+2x-8)=-(x ^{2}+4x-2x-8)=-(x+4)(x-2)\] hope its correct

Answer 4

roots are -4,2

Answer 5

how'd you get the 4x