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Before we start, recall : . Complete the “mental math” chart below:. C= ∏D . C= 2∏r . Arc Length. During today’s lesson you will solve problems involving arc length. Definition: Arc Length. length of an arc ( arc length ) .
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Before we start, recall: Complete the “mental math” chart below: C= ∏D C= 2∏r
Arc Length During today’s lesson you will solve problems involving arc length.
Definition: Arc Length length of an arc (arc length) The _______________________is a fractional part of a circle’s circumference. Many people confuse arc lengthwith arc measure. They are not the same. 45◦ Note: Every arc has a measure of __. The lengths of the arcs are ________________. different
Formula: Arc Length Arc Length is a fractional part of circumference. x A. L. = ПD22 2Пr22 Arc◌ / 360
Example: Arc Length If the radius is 24 cm and m < BTA = 60, then what is the length of AB? 60◌
ALERT! Determine these two things before writing the formula: 1. Arc measure , and 2. circumference (2П r or П D). O If the length of ROT is 116 П meters, what is the radius of the circle? R T
HOMEWORK Arc Length WS: Be sure to write the formula, then substitute necessary information before solving. Show ALL work on a separate sheet of paper to receive full credit.