I have this problem in my text book and i need to know how to do it,, my teacher didnt really explain how to do it in class before the bell rang, so im very much lost. i have to find the measure of each interior angle and its a quadrilateral angle Q is (2x+ 5) degrees, angle T is x degrees, angle S i s(2x+ 7) degrees, and angle R is x degrees. how do find my answer?
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Sum of the Measures of the Interior of angles
- Thread starter megie
- Start date
There is a theorem about the sum of the interior angles of a convex polygon. It should be in your book. If n is the number of sides of the polygon, the sum of the interior angles is (2n - 4) * 90 degrees. So what is the sum of the interior angles of a quadrilateral?I have this problem in my text book and i need to know how to do it,, my teacher didnt really explain how to do it in class before the bell rang, so im very much lost. i have to find the measure of each interior angle and its a quadrilateral angle Q is (2x+ 5) degrees, angle T is x degrees, angle S i s(2x+ 7) degrees, and angle R is x degrees. how do find my answer?
Can you solve the problem now?
HallsofIvy
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If you do not know a general formula, then you should at least know that a rectangle has four right angles so the total measure of its angles is 4(90)= 360. And you pretty much have to assume every quadrilateral has the same total angle measure in order that this problem have a solution.I have this problem in my text book and i need to know how to do it,, my teacher didnt really explain how to do it in class before the bell rang, so im very much lost. i have to find the measure of each interior angle and its a quadrilateral. angle Q is (2x+ 5) degrees, angle T is x degrees, angle S i s(2x+ 7) degrees, and angle R is x degrees. how do find my answer?
So add up 2x+ 5, x, 2x+ 7, and x, set that equal to 360, and solve for x.
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I have this problem in my text book and i need to know how to do it,, my teacher didnt really explain how to do it in class before the bell rang, so im very much lost. i have to find the measure of each interior angle and its a quadrilateral angle Q is (2x+ 5) degrees, angle T is x degrees, angle S i s(2x+ 7) degrees, and angle R is x degrees. how do find my answer?
The (2n - 4) * 90 degrees formula that JeffM provided is probably more well known as (n - 2) * 180 degrees in most textbooks in case you try and search for Jeff's formual and don't find it.
There is a theorem about the sum of the interior angles of a > > convex polygon. < <
It should be in your book. If n is the number of sides of the polygon, the sum of the interior angles is (2n - 4) * 90 degrees.
So what is the sum of the interior angles of a quadrilateral?
Can you solve the problem now?
That theorem also applies to non-convex polygons.
Thanks. I did not know that. Not sure that I ever studied non-convex polygons. I'll try to remember.That theorem also applies to non-convex polygons.