Radius of the circle = r = 6.4 cm
Length of the arc = s = 8 cm
Measure of angle formed by the arc = θ = ?
The radius of the circle, arc length and the angle made by the arc at the center of the circle are related by the equation:
s = rθ
From here we can find θ by:
θ = s/r
Using the values, we get:
θ = 8/6.4
θ= 1.25 radians
Thus the radian measure of the angle θ made by the arc will be 1.25 radians