SOLUTION: In a quadrilateral ABCD, the interior angles marked A, B, C, and D are in the ratio 6:7:8:9. Find the greatest interior angle and the greatest exterior angle.

Algebra ->  Parallelograms -> SOLUTION: In a quadrilateral ABCD, the interior angles marked A, B, C, and D are in the ratio 6:7:8:9. Find the greatest interior angle and the greatest exterior angle.      Log On


   



Question 1069216: In a quadrilateral ABCD, the interior angles marked A, B, C, and D are in the ratio 6:7:8:9. Find the greatest interior angle
and the greatest exterior angle.

Answer by ikleyn(53763) About Me  (Show Source):
You can put this solution on YOUR website!
.
In a quadrilateral ABCD, the interior angles marked A, B, C, and D are in the ratio 6:7:8:9. Find the greatest interior angle
and the greatest exterior angle.
~~~~~~~~~~~~~~~~~~~~~~~

The first phrase of the condition means that there is a common measure angle "x" such that

A = 6x, B = 7x, C = 8x, and D = 9x.

Since the sum of interior angles of any quadrilateral is 360 degs, you have this equation

6x + 7x + 8x + 9x = 360,   or

30x = 360,   hence,   x = 360%2F30 = 12 degs.

Then the greatest interior angle is 9x = 9*12 = 108 degs.

Answer.  The greatest interior angle is D = 108 degs.
         The greatest exterior angle is 180 - 6x = 180 - 72 = 108 degs.