Solve each quadratic equation by factoring and check

hello : 
the discriminat of each quadratic equation : ax²+bx+c=0 (a ≠ 0) is :
Δ = b² -4ac
1 )  Δ > 0  the equation has two reals solutions : x1,2 =  (-b±√Δ)/2a

ax²+bx+c = a(x-x1)(x-x2)
2 ) Δ = 0 : one solution : x1 = x2 = -b/2a

ax²+bx+c = a(x-x1)²
3 ) Δ < 0 : no reals solutions... no 

answer

the correct answer is

explanation

the given function is

the excluded values are obtained by solving:

we factor to obtain:

the excluded values are