Question

name:finding perimeter and area of irregular rectangular shapesdirections: find the perimeter and the area of each irregular rectangular shape below.be sure to express perimeter in terms of units and area in terms of square units.1.)p = ____ a = __2.)p = __ a = __3.)p = __ a = __4.)p = __ a = __5.)p = __ a = __6.)p = __ a = ____

Explanation:

1.)

Step1: Calculate perimeter

Add all outer side lengths.
$P = 20 + 9 + 16 + 4 + (20-16) + (9-4)$
$P = 20 + 9 + 16 + 4 + 4 + 5 = 58$

Step2: Calculate area

Subtract small rectangle area from large rectangle area.
$A = (20 \times 9) - ((20-16) \times (9-4))$
$A = 180 - (4 \times 5) = 180 - 20 = 160$

2.)

Step1: Calculate perimeter

Add all outer side lengths.
$P = 20 + 18 + 17 + 9 + (20-17) + (18-9)$
$P = 20 + 18 + 17 + 9 + 3 + 9 = 76$

Step2: Calculate area

Subtract small rectangle area from large rectangle area.
$A = (20 \times 18) - ((20-17) \times (18-9))$
$A = 360 - (3 \times 9) = 360 - 27 = 333$

3.)

Step1: Calculate perimeter

Add all outer side lengths.
$P = 21 + 12 + 11 + 5 + (21-11) + (12-5)$
$P = 21 + 12 + 11 + 5 + 10 + 7 = 66$

Step2: Calculate area

Subtract small rectangle area from large rectangle area.
$A = (21 \times 12) - ((21-11) \times (12-5))$
$A = 252 - (10 \times 7) = 252 - 70 = 182$

4.)

Step1: Calculate perimeter

Add all outer side lengths.
$P = 25 + 8 + 25 + 3 + (25-25) + (8-3)$
$P = 25 + 8 + 25 + 3 + 0 + 5 = 66$

Step2: Calculate area

Subtract small rectangle area from large rectangle area.
$A = (25 \times 8) - ((25-25) \times (8-3))$
$A = 200 - (0 \times 5) = 200 - 0 = 200$

5.)

Step1: Calculate perimeter

Add all outer side lengths.
$P = 30 + 28 + 21 + 7 + (30-21) + (28-7)$
$P = 30 + 28 + 21 + 7 + 9 + 21 = 116$

Step2: Calculate area

Subtract small rectangle area from large rectangle area.
$A = (30 \times 28) - ((30-21) \times (28-7))$
$A = 840 - (9 \times 21) = 840 - 189 = 651$

6.)

Step1: Calculate perimeter

Add all outer side lengths.
$P = 21 + 22 + 21 + 9 + (21-21) + (22-9)$
$P = 21 + 22 + 21 + 9 + 0 + 13 = 86$

Step2: Calculate area

Subtract small rectangle area from large rectangle area.
$A = (21 \times 22) - ((21-21) \times (22-9))$
$A = 462 - (0 \times 13) = 462 - 0 = 462$

Answer:

1.) $P = 58$ units, $A = 160$ square units
2.) $P = 76$ units, $A = 333$ square units
3.) $P = 66$ units, $A = 182$ square units
4.) $P = 66$ units, $A = 200$ square units
5.) $P = 116$ units, $A = 651$ square units
6.) $P = 86$ units, $A = 462$ square units