Answer:
ABC shaded area = 36 - 72 cm²
ABC shaded area perimeter = cm
ABCD area = cm²
ABCD perimeter = cm
Step-by-step explanation:
<u>Shape ABC</u>
Assuming you want the area and perimeter of the shaded part of the shape only...
<u>Area</u>
Area of a sector = (where r is the radius and
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⇒ area of a sector =
Area of triangle = 1/2 x base x height
⇒ area of triangle = 1/2 x 12 x 12 = 72 cm²
Therefore, area of shaded area = area of sector - area of triangle
⇒ area = 36 - 72 cm²
<u>Perimeter</u>
Arc length = (where r is the radius and
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⇒ arc length =
Hypotenuse of triangle = (where a and b are the legs of the right triangle)
⇒ hypotenuse = cm
Therefore, perimeter = arc length + hypotenuse
⇒ perimeter = cm
<u>Shape ABCD</u>
<u>Area</u>
Area of a semicircle = (where r is the radius)
⇒ area of large semicircle ABC =
⇒ area of small semicircle AD =
⇒ area of shape ABCD =
<u>Perimeter</u>
1/2 circumference =
⇒ perimeter =