Step 1: Concept
Perimeter of a rectangle = 2( L + W)
L = length
W = width
Area of a rectangle = Lenght x Width
Step 2:
Given data
The perimeter of a rectangle = 138
Length L = m
Width W = m - 5
Step 3:

Step 4:
Length = 37
Width = 37 - 5 = 32
Step 5:
Find the area
Area = length x width
Area = 37 x 32
Area = 1184
Final answer
Area of the rectangle = 1184