Question

smaller arc has a radius of 6cm and larger arc has a radius of 9cm.The central angle of both of the arcs is 90.Find the perimeter of the shape.​

Answer 1

Step-by-step explanation:

lenth of larger arc=

$\frac{2\pi \:r}{4} = \frac{2 \times \pi \times 9}{4} = 4.5\pi$

length of smaller arc=

$\frac{2\pi \: r}{4} = \frac{2 \times \pi \times 6}{4} = 3\pi \: cm$

thickness=9-6=3cm

perimeter of shape = lenth of larger arc +lenth of smaller arc + 2×thickness

=4.5π+3π+2×3

=7.5π+6

=29.57cm