A chess board is an 8 by 8 grid of squares. If you randomly choose 3 squares on the board, what is the probability that they lie on the same line, excluding diagonal lines? And if they lie on a diagonal line?

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.