# Geometry - angles of polygons

• Jul 28th 2008, 09:07 AM
kerilynn
Geometry - angles of polygons
Find the measure of each interior angle using the given information.

m<E = X
m<F = (X+20)
m<G = (X+5)
m<H = (x-5)
m<J = (X+10)

ok this is how far ive gotten

360 = m<e + m<f + m<g + m<h + m<J

360 = X + (X+20) + (x+5) + (x-5) + (x+10)

Now you are suppossed to combine like terms but iam not sure how to combine these

• Jul 28th 2008, 09:36 AM
Plato
Why do you have the sum of the interior angles equal 360?
There are five angles. So take a look at the following webpage.
Polygon -- from Wolfram MathWorld
On that page look a equation (4).
• Jul 28th 2008, 09:36 AM
abender
What kind of polygon is this? How can you assume that the 5 angles equal 360? If this is a quadrilateral, then the sum of the interior angles is 360. If it is a pentagon, then the sum of the interior angles is 360+180=540. And so forth. You have five interior angles given. I would assume this would be a pentagon. In this case, m<e + m<f + m<g + m<h + m<J = 540.

Then, x + (x+20) + (x+5) + (x-5) + (x+10) = 540.

Solve for x just like an algebra 1 problem. Then plug in x for each of your five interior angles to get your exact values.

If there is additional information to this problem, please mention it. Good luck.
-Andy