Angles
角度
Let's think about a triangle.
让我们想想三角形。
A triangle has three points, at each point, two lines meet together, this point is called an angle.
三角形有三个顶点,每个顶点连接着两条线,这个顶点就叫做角。
How do people measure an angle?
你知道人们如何测量角度吗?
Angles are measured in degrees.
角度是以度数来衡量的。
Do you know what a surprising fact is?
你知道一个惊人的事实吗?
Do you want to know a surprising fact?
你想知道这个惊人的事实吗?
Let's add three endpoint angles of a triangle, the sum will always be 180°.
无论三角形的形状和大小怎么样,
No matter what the shape or the size of the triangle.
三角形的三个内角加起来总是180°。