By rename do you mean turn into an improper fraction?
if so, it is because without turning it into an improper fraction, you cannot subtract 3/4 from 1/4 because you would get a negative answer and that would be incorrect
Since M is the midpoint of the segment AB
then measure of AM and MB are equal. So to solve the value of x, equate the following
measurement
AM = MB
50 – 3x = -20 + 4x
70 = 7x
<span>X = 10</span>
