Here we look at squaring expressions that involve radicals because people tend to make some common mistakes while solving such expressions. Take 5 times the square root of y quantity squared, the answer here is not 5y. Here's the reason, square means to multiply something with itself so the square of 5 root y would be 5 root y into 5 root y. So 5 x 5 is 25 and under root y into under root y equals just y so the answer will be 25y.
Now take under root of (x-3) being added into 7 quantity squared. This will not be x-3+49. The reason for this is that you can't distribute a square over addition. Now the same principle will apply here, both under root of (x-3) and 7 have to be multiplied separately to under root of (x-3) added into 7 with a plus sign in the middle. It will be simplified to a three term answer with the radical still there.
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