The highlighted part of the triangle is an angle. It is on the inside of the triangle and formed by two sides coming together.
Hope this helps! :)
Answer:
Angle
Step-by-step explanation:
Vertices (plural for vertex) are basically the points of the triangle.
Angles are the amount of space between two line segments (typically measured in degrees)
Sides are line segments of a shape.
Therefore, B is right.
x=4
since triangles are proportional by 2:1, then:
16/2=3x-4
8=3x-4
3x=12