Answer:
Types of polygon
Polygons can be regular or irregular. If the angles are all equal and all the sides are equal length it is a regular polygon.
Regular and irregular polygons
Interior angles of polygons
To find the sum of interior angles in a polygon divide the polygon into triangles.
Irregular pentagons
The sum of interior angles in a triangle is 180°. To find the sum of interior angles of a polygon, multiply the number of triangles in the polygon by 180°.
Example
Calculate the sum of interior angles in a pentagon.
A pentagon contains 3 triangles. The sum of the interior angles is:
180 * 3 = 540
The number of triangles in each polygon is two less than the number of sides.
The formula for calculating the sum of interior angles is:
(n - 2) * 180 (where n is the number of sides)
Answer:
{HH, HT, TH, TT}
Step-by-step explanation:
The set of all possible outcomes in tossing a coin twice is;
{HH, HT, TH, TT}
In the first toss the coin may land Heads. In the second toss the coin may land Heads or Tails. This can be represented as;
HH, HT
Heads in the first and second tosses. Heads in the first toss followed by a Tail in the second toss.
In the first toss the coin is also likely to land Tails. In the second toss the coin may land Heads or Tails. This can be represented as;
TH, TT
Tails in the first toss followed by a Head in the second toss. Tails in the first and second tosses.
Combining these two possibilities will give us the set of all possible outcomes in tossing a coin twice is;
{HH, HT, TH, TT}
4.5 and 3.25 gets you to 7.75, you are correct
Answer:
∠1 = 50°
∠2 = ∠3 = 130°
Step-by-step explanation:
In an isosceles trapezoid, such as this one, the angles at either end of a base are congruent:
∠1 ≅ 50°
∠2 ≅ ∠3
The theorems applicable to transversals and parallel lines also apply to the sides joining the parallel bases. In particular, "consecutive interior angles are supplementary." That is, angles 1 and 2 are supplementary, for example.
∠2 = 180° -∠1 = 180° -50° = 130°
We already know angle 3 is congruent to this.
∠1 = 50°
∠2 = ∠3 = 130°
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<em>Additional comment</em>
It can be easier to see the congruence of the base angles if you remove the length of the shorter base from both bases. This collapses the figure to an isosceles triangle and makes it obvious that the base angles are congruent.
Alternatively, you can drop an altitude to the longer base from each end of the shorter base. That will create two congruent right triangles at either end of the figure. Those will have congruent corresponding angles.
