Question

X² – 8x +16=0
using the quadratic formula

Answer 1

x = 4 (repeated root)

Explanation:

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

x = [-b +- sqrt(b² - 4ac)]/2a

x = [-(-8) +- sqrt[(-8)² - 4(1)(16)]/2

x = [8 +- 0]/2

x = 4, 4

Answer 2

x = 4

Explanation:

The quadratic formula is:

x = (-b ±
`\sqrt{b^(2) - 4ac}`)/2a

I learned it to the tune of pop goes the weasel! Songs really help you remember long formulas.

This quadratic formula is in the format ax²+bx+c = 0

So you just plug in the information!

x = (-(-8)±
`√(64-4(1)(16))`)/2(1)

x = (8 ±
`\sqrt{0`)/2

So, x = 8/2 = 4