chicagocubsrule wrote:

(sqrt(9 +sqrt80) + sqrt(9-sqrt80))^2

The square root of the sum of 9 and the square root of 80 plus the square root difference (so subtraction) between 9 and the square root of 80 (so the 9’s are under one radical (initial square root) and the 80’s are under 2 radicals.

a) 1

b) 9 – 4(5)^1/2

c) 14

d) 18

e) 20

Chicago - it would be easier to read if u use "m"

questions-about-posting-84537.html#p636437reading the question itself took half of my energy - LOL

BTW I got 20 too

here we are applying the formulas

(a+b)^2 = a^2+2ab+b^2and

(a+b)(a-b) = a^2-b^2 _________________

Thanks, Sri

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