A hiker begins a climb up a mountain at an altitude of 50ft above sea lea level. He climbs 20 ft per minute for 2 hours. What was the hiker's final altitude?

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.

The right answer should be 6 but your not very specific