<span>- 3/5 + - 3/4 Multiply the fractions until both fractions have the same common denominator. Also, when you add a negative number, it's basically the same as subtracting that number as well. - 12/20 - 15/20 Subtract the numerators but NOT the denominators. Final Answer: -27/20 or -1 7/20 *Both answers are equivalent to each other.</span>