We know that [tex]WZ[/tex] is the diameter of circle, so [tex]\angle ZCW = 180^{\circ}[/tex]. By knowing that central angles have the same degree value as the arcs they form by intercepting the circle, we now know that arc [tex]ZRW = \angle ZCW = 180^{\circ}[/tex]. So, the arc [tex]ZWX=ZRW+WX=180^{\circ}+63^{\circ}=243^{\circ}[/tex]
