An equilateral triangle is inscribed in a circle of radius 10 cm. Find :
(A) the area of the triangle.
(B) the area shaded
plz answer fasttt! ITS URGENT
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consider a Triangle ABC and height AD on AD point O centre on circle lies.
O is centroid that divides median AD in 2:1 ratio.
i.e. AO = 10 so OD = 5 so AD = 10 + 5 = 15
Now it is equilateral triangle so all angles are 60°.
height of triangle = (√3/2) × side
15 = √3/2 side
side = 30/√3
area = 1/2 base × height
= 1/2 × 30/√3 × 30/√3
= 450/3 = 150 cm²
O is centroid that divides median AD in 2:1 ratio.
i.e. AO = 10 so OD = 5 so AD = 10 + 5 = 15
Now it is equilateral triangle so all angles are 60°.
height of triangle = (√3/2) × side
15 = √3/2 side
side = 30/√3
area = 1/2 base × height
= 1/2 × 30/√3 × 30/√3
= 450/3 = 150 cm²
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