



 
Hi, Suppose the length of the arc is $a$ units and the measure of the angle is $\theta$ units. You can use degrees or radians, it's your choice. Write $a$ in terms of $a$ and $r.$ The perimeter of the sector is $a + 2r.$ Since the length of the arc is half the perimeter you have a equation relating $r$ and $\theta.$ Solve for $\theta.$ What is the area of the sector? Penny  


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