3. Definition of Triangle, Interier, Exterior, Boundary oftes
drawing the diagram, Perimeter.
I don't know what it means
Answers
Step-by-step explanation:
Interior Angles
First, we should define what X is. If you're looking for a missing puzzle piece, you need to know what it is you need. X is an interior angle. An interior angle is an angle inside a shape. Since triangles have three angles, they have three interior angles.
In this triangle below, angles A, B and C are all interior angles.
Just as the pieces in a jigsaw puzzle fit together perfectly, the interior angles in a triangle must fit with each other.
The sum of the interior angles is always 180 degrees. In other words, a + b + c = 180 degrees.
Let's prove this. Below are two parallel lines. Let's add a triangle between them. At the top of our triangle, we have three angles based around our line. Let's label them X, Y and Z. These three angles form a straight line, so they add up to what? 180 degrees.
Since we have a parallel line at the bottom of our triangle, we have alternate interior angles. So, the inside angle at the bottom is also equal to X. Z has an alternate interior angle at the bottom. And look what we did. We just proved that the sum of the interior angles of a triangle is 180 degrees.