How do you simplify 2 sqrt 20 + 45 sqrt20?

1 Answer
Mar 4, 2016
  • Factorize inside the square roots
  • Use some simple root rules
  • Voilá!

Explanation:

So we have 2sqrt(20) + 45sqrt(20)

Let's factorize a bit..

2sqrt(2 * 2 * 5) + 45sqrt(2 * 2 * 5)

= 2sqrt(4 * 5) + 45sqrt(4 * 5)

= 2sqrt(4) * sqrt(5) + 45 sqrt(4) * sqrt(5)

= 2 * 2 sqrt(5) + 45 * 2 sqrt(5)

= 4sqrt(5) + 90 sqrt(5)

= 94 sqrt(5)