Posted by Brianna on Sunday, December 12, 2010 at 2:19pm.
can someone please answer these questions for me?:
1. if the measure of an interior angle of a regular pentagonis 108 degrees, then the angle sum of that regular pentagon must be:
A. 120 degrees
B. 360 degrees
C. 540 degrees
D. 720 degrees
2. is it possible for a parallelogram to have a 38 degree angle and a 145 degree angle? explain please
3. a rectangle has a perimeter of 24 centimeters. one of its sides is 8 centimeters long. what are the dimensions of the rectangle? explain please
4. is it possible for a triangle to have angles with measures of 40 degrees, 115 degrees and 30 degrees? please explain
thanks :D sorry if theres soo many questions, i just really need help
- math - Reiny, Sunday, December 12, 2010 at 2:54pm
sum of interior angles = 180(n-2) where n is the number of sides
so each angle is 180(n-2)/n
180(n-2)/n = 108
180n - 360 = 108n
72n = 360
n = 5
So you have a pentagon
angle sum = 180(5-2) = 540
do the others the same way.
Remember in #2, that n has to be a whole number.
(e.g. A pentagon cannot have 4.3 sides)
#3. Just think about it again.
you have one of the sides.
How does one find the perimeter?
Answer this Question
More Related Questions
- geometry - 1. An exterior angle of a regular polygon measures 30 degrees. What ...
- Geometry - 1. How many sides does a regular polygon have if one exterior angle ...
- MATH - The exterior angle of a regular polygon is the angle formed by an ...
- 7th Grade Math - What is the measure of an exterior angle of a regular polygon ...
- Math - The measure of each interior angle of a regular polygon with n sides is...
- Geometry - In a regular polygon (equal sides and angles), you use (n-2)180 to ...
- math--fast help please - Find the interior and exterior angle measurements of a ...
- Algebra 2 - The formula A = 180(n-2)/n relates to the measure A of an interior ...
- geometry - 1. the sum of the interior angle measures of a convex dodecagon. 2. ...
- math - The measure of an interior angle of a regular polygon is 135 degrees. ...