How do you find the discriminant and how many and what type of solutions does x^2-8x+16=0 have?

1 Answer
May 3, 2015

The equation is of the form color(blue)(ax^2+bx+c=0 where:

a=1, b=-8, c=16

The Disciminant is given by :
Delta=b^2-4*a*c
= (-8)^2-(4*1*16)
= 64-64=0

If Delta=0 then there is only one solution.
(for Delta>0 there are two solutions,
for Delta<0 there are no real solutions)

As Delta = 0, this equation has ONE REAL SOLUTION

  • Note :
    The solutions are normally found using the formula
    x=(-b+-sqrtDelta)/(2*a)

As Delta = 0, x = -b/(2a) = -(-8)/(2*1) = 8/2 = 4

x = 4 is the solution