Question 768055
Quadrant 2, the actual angle is {{{pi-referenceAngle}}}.
{{{arcsin(4/5)}}} gives the reference angle from 0 to pi.  You would want first, {{{x=pi-arcsin(4/5)}}}
and then you are looking for {{{2x}}}, so
{{{highlight(2(pi-arcsin(4/5)))}}}.



Approximately 253.7 degrees.