Justin’s doctor said that the expression x+y+5/2, where x and y are his parents’ current heights in inches, gives an estimate of how tall justin will be as an adult. justin’s work evaluating the formula is shown below. mom’s height = 54 inches dad’s height = 71 inches 71+54+5/2 = 71+27+5=130 inches what error did justin make? he should have made x equal 54 and y equal 71. he should have added the values in the numerator before dividing by 2. he should have divided the 71 by 2 instead of the 27. he should have made the numerator 76 + 59.