Which identity could be used to rewrite the expression x^4-100?

A) Quadratic formula

B) Two squares

C) sum of cubes

D) Difference of squares

Answer: D: difference of squares (apex)

Given the polynomial of degree 4, this can be written as:

x^4-100

let

x^2=a

thus the expression can be written as:

a^2-100

this is a polynomial of degree 2 also known as quadratic equation.

Hence the answer is:

A) Quadratic formula