3 times a number is 54 less than the square of that number

3x = x^2 - 54
x^2 - 3x - 54 = 0
(x - 9)(x + 6) = 0
The answer is 9 or -6

First step is to get rid of the square root. remember that a square root is the same as raising to the (1/2) power. see below: multiply exponents per exponent rules to get: remember you subtract exponents from the denominator and add exponents in the numerator so: simplify further: so a is the correct choice. if you don't understand this google exponent rules and it will you understand. look at the image results.