Question

I can’t seem to figure out the step by step

Answer 1

Explanation:

(√2 + 2√5) (√4 - 2√5)

= (√2 + 2√5) (√2² - 2√5)

= (√2 + 2√5) (2 - 2√5)

= √2 (2 - 2√5) + 2√5 (2 - 2√5)

= √2x2 + √2x(-2√5) + 2√5x2 + 2√5x(-2√5)

= 2√2 - 2√10 + 4√5 - 4√5²

= 2√2 - 2√10 + 4√5 - 20

= -14.55