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today i took my grade 9 EQAO math test and this was a question on it, the hardest on the test it gave me a picture of a five point star (drawn as you would without lifting the pecnil, with five lines). I had to solve for angles abcde (the angles within the point of the star) withough a protractor, and no measurements given. impossible you may say, but there is a sure way that is the same for a star of any size first thing you must realize is that when you draw a star, a pentagon is formed in the middle, with 5 isoscles triangles off each side. step 1: find the angle of each side of the pentagon if you didn't already know, the formula for finding each angle of a regular shape is, with n being the number of sides in the shape is: 180(n - 2) / n. Of course if you plug in 5 that will make 180(3) / 5, 540 / 5, so 108 degrees. step 2: fromm that find two of the three angles of each triangle in the star it can be done quite easily. looking at any of the five lines, you could, and this isn't easy to explain withough pictures, but on any of the lines you will see 108 degress, and it is clear that the total between that angle and the base angles in the triangle add up to 180. So each of the base angle sof the triangle are 72 degress. draw it and it will be clear sorry i can't explain this well. step 3: find the third angle of the triangle you should know how to do this. the three angles of a triangle add up to 180 always so u subtract the two known angles from 180 to find the third. since 180 - 72 - 72 = 36, that is the angle of each point. so, angles abcde (which must be equal) = 36 degrees
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What has 5 sides of equal length?
A regular pentagon. A regular pentagon has five sides of equal length and its five angles are also equal. The term regular implies the notion of equal sides and equal angles.
What has 5 angles and five sides that do not all measure the same?
A shape with five angles and five sides that do not all measure the same is an irregular pentagon. A regular pentagon has all five sides and angles the same size.
How many pairs of vertical angles are formed if three lines at a point?
five
If the exterior angle of a regular polygon is 108 degrees how many sides does the polygon have?
That's true if the interior angles are 108 degrees, but a regular polygon cannot have exterior angles of 108 degrees.
What is a polygon with five sides and five angles?
a pentagon has five sides and five angles.
A regular pentagon has how many angles?
Every pentagon, regular or not, has five interior angles and five exterior angles.
How many angles does a pentagon?
A pentagon has five angles and five sides. The interior angles of a regular pentagon add up to 540 degrees.
Does a pentagon have five equal angles?
Regular pentagons do.
What has 5 sides of equal length?
A regular pentagon. A regular pentagon has five sides of equal length and its five angles are also equal. The term regular implies the notion of equal sides and equal angles.
Does a pentagon have obtuse angles?
Yes a regular pentagon has five interior angles of 108 degrees
What are the sizes of angles in a pentgonal pyramid?
A regular pentagonal pyramid is composed of five equilateral triangles and one regular pentagon. Each equilateral triangle has three angles of 60 degrees each. The regular pentagon has five internal angles of 108 degrees each.
What has 5 angles and five sides that do not all measure the same?
A shape with five angles and five sides that do not all measure the same is an irregular pentagon. A regular pentagon has all five sides and angles the same size.
What is a regular two dimensional shape?
A two-dimensional shape (polygon) is said to be "regular" (or equilateral) if all its sides are the same length and all its angles are the same angle. A regular pentagon, for example, has 72-degree angles on all five angles, and all its five sides are the same length.
What polygon has two right angles and five sides?
An irregular pentagon is a polygon that has five sides and two right angles. A regular polygon on the other hand does not have right angles.
A polgon with 5 equal sides and angles?
The name of a regular polygon with five equal sides and five equal angles is a pentagon. Each of the internal angles is equal to 108 degrees.
Are there any figures that have only three right angles?
No REGULAR polygon can have three right angles in it. Any polygon with five or more sides CAN have three right angles, as long as it's not regular.
How many angles are inside a pentagon?
There are five angles within a pentagon and in a regular one each angle is 108 degrees.
