Question

What is the discriminant of `x^2 + 8x + 16 = 0` and what does that mean?

Answer 1

The expression is of the form `Ax^2+Bx+C=0`
where `A=1,B=6,C=16`

Explanation:

The discriminant is defined as `D=B^2-4AC`
If `D>0` there are two solutions to the equation
If `D=0` there is one solution
If `D<0` there is no solution (in real numbers)

In your case `D=8^2-4*1*16=0->`one solution.

The equation can be written as `(x+4)^2->x=-4`