To convert x radian to degrees, the formula used is,
[tex]xrad=x\times\frac{180^{\circ}}{\pi}[/tex]Hence, 9π/4 rad can be converted to degrees as,
[tex]\frac{9\pi}{4}\times\frac{180^{\circ}}{\pi}=405^{\circ}[/tex]Therefore, 9π/4 rad is equal to 405 degrees.
