Question 867053
If cut out the rectangle piece in the middle, you have on each end, a right triangle of sides 10, 4, and height.  Cosine of the undisturbed corner of the trapezoid is {{{4/10}}}.


u = measure of the undisturbed angle corner of trapezoid;
{{{cos(u)=2/5}}}
{{{2u=2*arccos(2/5)}}} takes care of angle measures of both angles of the longer base.
{{{u=66.42}}} degrees
{{{2u=132.84}}} degrees
{{{360-132.84=227.16}}}
if v = the other angle, then {{{v=227.16/2=113.58}}}.


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Two base angles are 66.42 degrees each
and other two base angles are 113.58 degrees each
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