Find the length of arc ab. Need help!!!
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Answer:
12.4cm (rounded to nearest tenth)
Step-by-step explanation:
To find the length of an arc, you have to find the circumference of the full circle itself multiplied by the angle of the arc over 360°. The circumference of a circle is pi × r × 2.
Length of arc = [tex]\frac{90}{360}[/tex] × 3.14 × 7.9 × 2
= 12.403
≈ 12.4cm (rounded to nearest tenth)