Lesson 1.1- Points. Lines and Planes Objective: The student will be able to make and describe fundamental sketches. The student will also be able to understand basic concepts such as intersect, horizontal, vertical, collinear and coplanar.

Points, Lines and Planes In geometry, a _________ is a location, a ________ contains points, and a __________ is a flat surface that contains points and lines. If points are on the same line, they are _________________. If points on are the same plane, they are _________________. Points, lines and planes are known as ____________________ terms because they can only be explained using examples and descriptions. We will use the following chart to provide examples and descriptions of the points, lines and planes.

PointLinePlane Model Drawn As a dot With an arrowhead at each end As a shaded, slanted figure Named by A ___________ letter. Two _________ representing points on the line or a lowercase letter A _____________ script letter or by using letters naming three noncollinear points Facts Has neither _________ nor __________ There is exactly one line through any two ______ Lines extend indefinitely in two directions. There is exactly one _________ through any three noncollinear points. Planes extend indefinitely in all directions. Words/Symbols point Pline n, line AB or _____, line BA or _________. plane T, plane XYZ, _______, ________

m N D C B A Use the figure to name each of the following: 1) A line containing point A __________________________________ 2) A plane containing point D __________________________________ Refer to the figure at the right. Use proper notation to answer the following: A C B D E L mP 3) Name a line that contains point A: ________ 4) What is another name for line m ? ________ 5) Name a point not on line l : __________ 6) Name a point not on line m : __________ 7) Name the intersection of AC and BD: ________ 8) Name a point not on line l or line m. _________

In the space at the right, draw and label separate figures that show each of the following: 9) Line AB is in plane Q 10) line ST intersects line AB at P. 11) Point X is collinear with points A and P. 12) Point Y is not collinear with points T and P. 13) Line l contains points X and Y.

Three Dimensional Drawings Three dimensional drawings are drawings that represent points, lines and planes as they appear in space. Because it is difficult to show three dimensions on a two dimensional page, separate planes are represented by different shades of color and hidden parts of lines and planes are represented by dotted lines. Refer to the figure at the right and answer questions How many planes appear in the figure? 2. Name them. 3. Name three points that are collinear. 4. Are points A,B,C and D coplanar? 5. At what point do BD and AC intersect? D C A B S