Question 1194230

Assuming that a 90° arc has an exact length of 5𝜋 in., find the length of the radius of the circle in inches
<pre>Circumference (entire arc length) of ANY circle: 2ꙥr
Arc length of this circle's 90<sup>o</sup> angle: 5ꙥ inches
Fraction of this circle's circumference equal to this arc length: {{{90/360}}} 
We then get: {{{matrix(3,3, (90/360)2pi*r, "=", 5pi, (1/4)2pi*r, "=", 5pi, 
(pi/2)r, "=", 5pi)}}} 
          <font color = red><font size = 4><b>Radius,</font></font></b> or {{{highlight_green(matrix(1,10, r, "=", 5pi/(pi/2), "=", 5pi*(2/pi), "=", 5cross(pi)*(2/cross(pi)), "=", highlight(10), inches))}}}</pre>