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Help please !!!!!!!!!!!!!!!!!!

Help please !!!!!!!!!!!!!!!!!!-example-1

1 Answer

5 votes

Answer:

n = 59

Explanation:

There's definitely a better way, i just did math randomly but here goes:

First i squared both sides. which gets you:


(√(n+5)-√(n-10) )(√(n+5)-√(n-10) )=1^2\\\\n+5 -2√((n+5)(n-10)) +n-10=1

Cleaning this up gives you:


2n-5 -2√((n+5)(n-10))=1

Now move everything to the other side so we can square this equation again


-2√((n+5)(n-10))=-2n+6

Divide both sides by -2


√((n+5)(n-10))=n-3

square again


(n+5)(n-10)=(n-3)^2\\n^2-5n-50=n^2-6n+9

subtract n^2 from both sides, add 6n, and add 50


-5n-50=-6n+9\\n-50 = 9\\n=59

Put this back into the equation and you get a correct answer!

sqrt(59 + 5) = sqrt(64) = 8

sqrt(59-10) = sqrt(49) = 7

8 - 7 = 1

User Dunk
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