How do you simplify #2 sqrt20 - 3 sqrt 7- 2 sqrtt 5 + 4 sqrt 63#?

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Answer 1 · 2018-01-15T16:17:31

#2sqrt5+9sqrt7#

I am presuming that there is a typo in the third term where instead of #-2sqrt5#, you have typed a double #t# to get #-2sqrtt5#.

Using that presumption, I shall calculate the above as:

#2sqrt20-3sqrt7-2sqrt5+4sqrt63#

Reduce the first and the last terms by first factorising and then removing the squares from under the square root sign.

#2sqrt(2xx2xx5)-3sqrt7-2sqrt5+4sqrt(3xx3xx7)#

#2xx2sqrt5-3sqrt7-2sqrt5+4xx3sqrt7#

#4sqrt5-3sqrt7-2sqrt5+12sqrt7#

Rearrange with the preceding signs to put like terms together.

#4sqrt5-2sqrt5+12sqrt7-3sqrt7#

#(4sqrt5-2sqrt5)+(12sqrt7-3sqrt7)#

#2sqrt5+9sqrt7#

If I have erred in my original presumption, this answer will not apply. :)