Question 1098035
A better restatement of the exercise is this:


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Quadrilateral ABCD has side AB parallel to side CD, and ratio of interior angle at A to that at B is 2:7, and the ratio of interior angle at C to that at D is 3:8.
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The given information that AB is parallel to CD makes possible finding four equations.


{{{system(A+D=180,B+C=180,A/B=2/7,C/D=3/8)}}}------four unknowns, four equations.  I leave the rest to you.

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{{{system(D=144*degrees,A=36*degrees,B=126*degrees,C=54*degrees)}}}.