SOLUTION: This one has kicked my skunk over and over! I know the answer is 4 & 20, but I cannot see how to arrive at that answer. 4y+20 under the radical sign

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Question 99003: This one has kicked my skunk over and over! I know the answer is 4 & 20, but I cannot see how to arrive at that answer.
4y+20 under the radical sign - y-4 under the radical sign = 6
I hope I explained that well enough. I tried to cut and paste the problem out of my Microsoft Word file but it did not work.
Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
4y+20 under the radical sign - y-4 under the radical sign = 6
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Rearrange:
sqrt(4y+20) = sqrt(y-4)+6
Square both sides to get:
(4y+20) = (y-4)+12sqrt(y-4)+36
12sqrt(y-4)= 4y+20-(y-4)-36
12sqrt(y-4) = 3y-12
4sqrt(y-4) = y-4
Square both sides to get:
16(y-4) = y^2-8y+16
y^2-24y+80 =0
(y-4)(y-20)=0
y = 4 or y = 20
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Check these answers in the original equation.
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Cheers,
Stan H.

SOLUTION: This one has kicked my skunk over and over! I know the answer is 4 & 20, but I cannot see how to arrive at that answer. 4y+20 under the radical sign - y-4 under the radical si