Lily deposited $500 in a savings account. at the end of 1 year, she had earned $20 in simple interest. what interest rate did she receive?

X/100 *500 = 20

500/100x = 20

5x = 20

x = 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.