If "the angle" means the angle between two radii at the centre, the answer is no. You need to know the circumference first. Then use radius = circumference divided by 2 x pi.
Multiply ( pi R2 ) by [ (angle included in the sector) / 360 ].
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You find central angle by using proportions. Part/Whole = x/360 Then, cross multiply and divide.
An angle that's vertex is on the center of the circle.