#### Transcript 1-1 Points, Lines, and Planes

**+**

### 1-1 Points, Lines, and Planes

**+**

### Real-Life

**+**

### Vocabulary

**Undefined Terms**- point, line, and plane are considered undefined terms because they are only explained using examples and descriptions **Point- **a location – it does not have shape or size (named by capital letter) **Line- **made up of points and has no thickness or width (named by a lowercase letter, or two points on the line) **Plane**- a flat surface made up of points that extends infinitely in all directions (named by a capital script letter, or 3 points in the plane) A P Q

*m*

J .

K .

L B .

**+**

### Vocabulary

**Collinear**- points that lie on the same line **Coplanar**- points that lie in the same plane **Intersection- **the set of points that two or more geometric figures have in common **Space- **a boundless, 3-D set of all points

**+**

### Examples

Line *g *; or line PN Line *j*; or line MT Plane *S*; or Plane TNQ

**+**

### Practice

Line *q* Point B or Point A Line DC Plane *G *or Plane ABD

**+**

### Examples

4. Draw and label a figure for AK and CG intersect at point M in plane *T*. C

*T*

M K A G 5. How many planes are shown?

**6**

6. Name 3 collinear points: SXM 7. Are points N, R, S, and W coplanar? Why (not)?

No. NRS all lie on plane *A, *but W is on plane WTQP

**+**

### Practice

4. Draw and label a figure for lines *q *and *f *intersect at point Z in plane U.

5. How many planes are shown?

**5**

6. How many of the planes contain points F and E?:

**2**

7. Name 4 points that are coplanar: FEAB, or EDCB, or CAFD