Math CentralQuandaries & Queries


Question from lauren, a student:

if the sum of the measures are 360 in a parallelogram. a and d are same measures, c and b are same too. If c is twice the measure of a what are all the angles?

Hi Lauren,

The sum of the measures of the angles is 360 degrees so a + b + c + d = 360. But you know that a = d and b = c so

2a + 2b = 360.

You also know that b = c = 2a so substitute b for 2a in the equation above and solve for b.


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