-5 remember: the quadratic formula is -b plus or minus the square root of b^2 - 4ac all over 2a
ax^2+bx+c=0
so
[-9(+/-) sq root of (-9^2 -(4*1*20))] / 2*1
[-9(+/-) sq rt (81-80)] / 2
[-9(+/-) sq rt of 1] / 2
[-9(+/-)1] / 2
then you do this for both + and -
(+)
(-9+1)/ 2
-4
(-)
(-9-1)/2
-5
so your answer is going to be -4 and -5
