Calculate Rectangle Perimeter: Finding the Distance Around ABCD with Multiple Measurements

Question

Look at the rectangle below:
AAABBBCCCDDDEEEFFF3654

Calculate the perimeter of rectangle ABCD.

Video Solution

Solution Steps

00:00 Calculate the perimeter of the rectangle
00:03 Opposite sides are equal in a rectangle
00:14 ED equals the side (AD) minus AE
00:25 Let's substitute appropriate values according to the given data and solve for ED
00:38 This is the value of side ED
00:43 Let's use the Pythagorean theorem in triangle EDF to find DF
00:54 Let's substitute appropriate values according to the given data and solve for DF
01:10 Let's isolate DF
01:28 This is the value of DF
01:32 The entire side (DC) equals the sum of its parts (DF+FC)
01:44 Let's substitute appropriate values and solve for side DC
01:48 This is the length of side DC
01:54 Opposite sides are equal in a rectangle
01:57 The perimeter of the rectangle equals the sum of its sides
02:04 Let's substitute appropriate values and solve for the perimeter
02:21 And this is the solution to the problem

Step-by-Step Solution

Since in a rectangle every pair of opposite sides are equal to each other, we can claim that:

BC=AD=6 BC=AD=6

Therefore:

ADAE=ED AD-AE=ED

Let's substitute the known data into the formula:

63=ED 6-3=ED

3=ED 3=ED

Let's focus on triangle EDF and find side DF using the Pythagorean theorem:

ED2+DF2=EF2 ED^2+DF^2=EF^2

Let's substitute the known data into the formula:

32+DF2=52 3^2+DF^2=5^2

9+DF2=25 9+DF^2=25

DF2=259 DF^2=25-9

DF2=16 DF^2=16

Let's find the square root:

DF=4 DF=4

Side DC=8

Since in a rectangle every pair of opposite sides are equal to each other:

AD=BC=6 AD=BC=6

AB=CD=8 AB=CD=8

Now we can calculate the perimeter of the rectangle by adding all sides together:

6+8+6+8=12+16=28 6+8+6+8=12+16=28

Answer

28