
The shape in part a) is shown below with the large rectangle completed.
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The area A of the given shape is calculated using 3 steps:
1) calculate the area of the large rectangle ABWF : A1 = Length × Width = 5 × 3 = 15 unit^{ 2}
2) Calculate the area of the small rectangle CWED : A2 = CW × WE = 3 × 1 = 3 unit^{ 2}
3) Subtract the area of the small rectangle from that of the large rectangle: A = A1  A2 = 15  3 = 12 unit^{ 2}

The shape in part b) is shown below with the large rectangle completed.
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The area A of the given shape is calculated using 3 steps:
1) calculate the area of the large rectangle GHZL : A1 = Length × Width = 5 × 3 = 15 unit^{ 2}
2) Calculate the area of the trapezoid JIZK : A2 = (1/2) × ZK × (IZ + JK) = (1/2) × 1 ×(2 + 3)
= (1/2) × 1 × 5 = (1/2) 5 = 5 / 2 = 2.5 unit^{ 2}
3) Subtract the area of the trapezoid from that of the large rectangle: A = A1  A2 = 15  2.5 = 12.5 unit^{ 2}

The shape in part c) is shown below with the large rectangle completed.
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The area A of the given shape is calculated using 3 steps:
1) calculate the area of the large rectangle QMNP : A1 = Length × Width = 5 × 3 = 15 unit^{ 2}
2) Calculate the area of the triangle NOP : A2 = (1/2) × H × NP = (1/2) × 2 ×3
= (1/2) × 6 = 3 unit^{ 2}
3) Subtract the area of the triangle from that of the large rectangle: A = A1  A2 = 15  3 = 12 unit^{ 2}

The shape in part d) is shown below with the large rectangle completed.
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The area A of the given shape is calculated using 4 steps:
1) calculate the area of the large rectangle RA_{1}BS : A1 = Length × Width = 5 × 3 = 15 unit^{ 2}
2) Calculate the area of the triangle RA_{1}V : A2 = (1/2) × RA_{1} × A_{1}V = (1/2) × 3 ×2 = (1/2) × 5 = 2.5 unit^{ 2}
3) Calculate the area of the triangle UBT : A3 = (1/2) × UB× BT = (1/2) × 1 ×1 = (1/2) = 0.5 unit^{ 2}
3) Subtract the areas of the two triangles from that of the large rectangle: A = A1  A2  A3 = 15  2.5  0.5 = 12 unit^{ 2}