Math 1 · Unit 11 · Lesson 3 · part 1 of 5
The Words We Use
The vocabulary for this lesson, in one place.
Words we use
| Word | Plain English | What you do |
|---|---|---|
| Perimeter | The distance all the way around a shape. | Distance for every side, then add. |
| Area | How much flat space a shape covers, in square units. | Rectangle: length times width. Triangle: one half base times height. |
| Base and height | For a triangle, a side and the perpendicular distance to the opposite corner. | Check perpendicular with slopes first. |
| Altitude | A segment from a corner that meets the opposite side at a right angle: the height. | Its slope is the negative reciprocal of the base's slope. |
| Vertex (vertices) | A corner of a shape. | Name the shape by its vertices in order. |
| Box method | Draw a rectangle around the shape on the grid lines, then subtract the corner pieces. | For shapes with no easy height. |