Question

find the answer please!​

Answer 1

anything which is eqal to zero is zero.

Answer 2

x²+x-20=0 by formula of quadratic equation

x=(-b±√(b²-4ac))/2a

x=-1±√{1-(-80)}/2

x= (-1±√81)/2

x=( -1±9)/2

x=4,-5