Thinking Mathematically Algebra: Graphs, Functions and Linear Systems 7.1 Graphing and Functions

Graphing Cartesian coordinates (Rene’ Descartes) X (horizontal), y (vertical axis) Four quadrants. A point is located on a graph by an ordered pair of coordinates (x, y) Two dimensional analog of the number line.

Example: Graphing Exercise Set 7.1 #5, 17 Plot the following points: (-3, -5) (3.5, 4.5) X Y (0,0)

Graphing Equations In Chpt. 6 we looked at equations in a single variable. For linear equations the solution is typically a single value. Now consider an equation in two variables, solutions will be pairs, an x value and a y value. An equation with two variables will typically have an infinite number of solution pairs. We can see these solutions visually by plotting them on a graph. The graph of an equation is the set of all points whose coordinates satisfy the equation

Example: Graphing Equations Exercise Set 7.1 #21, 23 Graph each equation. Select integers for x from -3 to 3. y = x 2 – 2 y = x - 2

Thinking Mathematically Algebra: Graphs, Functions and Linear Systems 7.1 Graphing and Functions