The path of a projectile launched from a 16-ft-tall tower is modeled by the equation y = −16t2 + 64t +16. What is the maximum height, in feet, reached by the projectile?

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.