Math 1 · Unit 4 · Lesson 4 · 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 |
|---|---|---|
| Right triangle | A triangle with one right angle. | Find two sides whose slopes multiply to −1; the right angle is where they meet. |
| Rectangle | Four right angles, and opposite sides parallel. | Opposite sides: equal slopes. Neighbors: slopes multiply to −1. |
| Parallelogram | Opposite sides parallel, corners not necessarily square. | Equal slopes for opposite sides only. |
| Parallel, perpendicular | Same slope; slopes that multiply to −1. | The two tests from Lessons 1 and 2, now applied to sides. |
| Prove with algebra | Back up a claim about a shape with numbers you computed, not with how it looks. | Compute every slope you need and show the test passes. |
| Distance, midpoint | The length of a side, and its center point. Unit 11. | Needed to show sides are equal (a square) or to find centers. Not slope's job. |