



 
Hi Dolly, You have named the angles a, b, c and d. I am going to use capital letters to represent the measures of the angles
Now look at the information in the problem and write it in terms of the letters A, B, C and D. the sum of the measure of the angles of a parallelogram is 360.angles
I think the next statement should be a and d have the same measure and b and c have the same measure
c is twice the measure of angle a
Now put this information together. If A = D and B = C then the first equation can be written
In the equation you have now, 2A + 2C = 360, you can substitute C for 2A. Solve the resulting equation for C. I hope this helps,  


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