Answer: C and D.
Step-by-step explanation: The pictures show the work. So sorry about the delay -- my computer wasn't letting me type formulas, so I hand-wrote. If you have questions, let me know and I'd be happy to clarify, and if the pictures are sideways, use the rotate button at the top right.
On the x axis means that the y value is 0 or the point is (x,0)
distance formula
D=

we know that distance is 5
the first point is (x1,y1)
the (x2,y2) is (x,0)
so
D=5
x1=-8
y1=3
x2=x
y2=0
5=

5=

5=

5=

square both sides
25=

minus 25 both sides
0=x^2+16x+48
factor
0=(x+4)(x+12)
set each to zero
x+4=0
x=-4
x+12=0
x=-12
the points are
(-4,0) and (-12,0)
Hello from MrBillDoesMath!
Answer:
0
Discussion:
For the quadratic ax^2 + b^x + c, the discriminant is b^2 - 4ac. In our case, the discriminant is
(-20)^2 - 4 (4)(25) =
400 - 4 (100) =
0
(This means the polynomial has a duplicate root. In fact it factors as (2x-5)^2 ).
Thank you,
MrB