Hello!
First you factor 28
2^2 * 7 = 28
Now we have

If you take a square root of a square number they cancel out

The answer is B)

Hope this helps!
First you would take one and move it over to the left side and never leave for why and then you divide by one which would leave for why and it would also have X equals 4Y and then you divide ask my Y and I will just leave you which is XY equals four
Because 10 divided by 6 equals 6 tenths not 6 hundredths