The temperature in a town is 36.9 degrees Fahrenheit during the day and negative 23.5 degrees Fahrenheit at night. Find the difference in the temperatures.

Subtract 23.5 from 36.9 which gives you 13.4. The differences in temperature is therefore 13.4

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.