Answer:
Step-by-step explanation:
Given
DG = r+3
GM = 4r-28
DM = 45
Based on the given parameters the equation DM = DG+GM is true.
TI get the value of r we will substitute the given values into the expression;
r+3+4r-28 = 45
5r -25 = 45
5r = 45+25
5r = 70
r = 70/5
r = 14
Hence the value of r is 14
