Question

Which of the expressions below could be factored quickly using the "difference of squares"? Select all that apply.

O 81x² - 12
O x^2 + 25
O 4x^2 – 25
O 9x^2 – 16
O x^2-50
O x^2-81
O x^2-100

Answer 1

• 81x² - 12, no as 12 is not a perfect square
• x^2 + 25, no as it is a sum of squares
• 4x^2 - 25, yes
• 9x^2 - 16, yes
• x^2 - 50, no as 50 is not a perfect square
• x^2 - 81, yes
• x^2 - 100, yes