Factor the expression. d2 - 4d + 4

Rewrite it in the form a^2 - 2ab + b^2, where a = d and b = 2

d^2 - 2 (d) (2) + 2^2

Use the Square of Difference: (a - b) ^2 = a^2 - 2ab + b^2

(d - 2) ^2

(d - 2) ²

Step-by-step explanation:

d² - 4d + 4 ← is a perfect square of the form

(x ± a) ² = x² ± 2ax + a²

compare coefficients of like terms

- 2a = - 4 ⇒ a = 2 and a² = 4, hence

d² - 4d + 4 = (d - 2) ²