http://img298.echo.cx/img298/2145/pentagon8zw.png ABCDE is a regular pentagon, in the previous question I worked out angle AEB to be 36°.. the next question has asked to prove that BCDE is a trapezium but I don't know how to. I figured it might be to do with showing that the sum of the angles in BCDE = 360° but that doesn't necessarily prove it is a trapezium. What if I showed angles DEB and EBC to be equal.. does that prove it?
Many thanks.
Many thanks.