Question

What angle does an arc 5.5cm in length sudtend at the centre of a circle of diameter 7cm.

Answer 1

Diameterof circle = 7cm

Then radius would be (r) = 3.5cm

l = 5.5cm

Arc length = (Ѳ/360)2∏r

5.5 = (Ѳ/360)2*3.14*3.5

5.5 = (Ѳ/360)21.98

Divide to each side by 21.98.

5.5/21.98 = Ѳ/360

Ѳ/360 = 0.25

Multiple to each side by 360.

Ѳ = 90

Arc angle is 90 degrees.