Math, asked by aakashpal, 1 year ago

in the given figure find the area of shaded region if AC is the diameter of semicircle on AC and BC is the radius of quadrant and BC=21& BD = 28​

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Answers

Answered by assalterente
27

Answer:

428.6 cm²

Step-by-step explanation:

Since in the given figure, our aim tis to find the area of shaded region if AC is the diameter of semicircle on AC and BC is the radius of quadrant and BC=21& BD = 28​.

The area of the shaded region is equal to the Area of Semi-circle plus the Area of triangle ABC minus the Area of quarter circle.

Thus:

Area of triangle = 1/2 x 21 x 28 = 294 cm²

Then in order to find area of semi-circle, we need to compute:

AC² = 28² + 21²

       = 1225

⇒ AC = 35

The radius of semi-circle is equal to 35/2 = 17.5

Then, we can conclude that the Area is equal to

1/2 x 3.14 x (17.5)² = 480.8 cm²

Thus the Area of quarter circle is equal to:

1/4 x 3.14 x 21²= 346.2 cm²

Area of shaded region = 294 + 480.8 - 346.2 = 428.6 cm²

Hence, our area is equal to 428.6 cm².

Answered by amitnrw
15

Answer:

Area of shaded Region = 428.75 cm²

Step-by-step explanation:

in the given figure find the area of shaded region if AC is the diameter of semicircle on AC and BC is the radius of quadrant and BC=21& BD = 28​

Area of Shaded region = Total Area - Arc area

Total Area = Area of Semi circle + Area of Triangle

Area of Triangle = (1/2) * Base * Height = (1/2) * 21 * 28 = 294 cm²

To find Area of Semi Circle , first we need to find radius

Radius = Diameter/2

Diameter is hypotenuse of triangle so using Pythagoras theorem

Diameter² = Base² + height²

=> Diameter² = 21² + 28²

=> Diameter² = 441 + 784

=> Diameter² = 1225

=> Diameter = 35 cm

Radius = 35/2

Are of Semi circle = (1/2) (22/7) (35/2)² = 11 * 5 * 35 / 4 = 481.25 cm²

Total Area = Area of Semicircle + Area Of Triangle

=> Total area = 481.25 + 294 = 775.25 cm²

Angle of arc = 90°  Radius = 21 cm

Area of Arc = (90/360) (22/7) × 21² = 11 * 3 * 21 / 2 = 346.5 cm²

Area of Shaded region = 775.25 - 346.5 = 428.75 cm²

Area of shaded Region = 428.75 cm²

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