Answer:
5 units
Step-by-step explanation:
The area of a sector is [tex]A=\frac{r^2\theta}{2}[/tex] where [tex]r[/tex] is the radius and [tex]\theta[/tex] is the angle formed:
[tex]A=\frac{r^2\theta}{2}\\\\\frac{75\pi}{16} =\frac{r^2(\frac{3\pi}{8})}{2}\\\\150\pi=16r^2(\frac{3\pi}{8})\\\\150\pi=6\pi r^2\\\\25=r^2\\\\5=r[/tex]
Therefore, the radius of the sector is 5 units
