Lesson: Solving Linear Equations Using Function Graphs Mathematics • 9th Grade

In this lesson, we will learn how to solve linear equations using function graphs and verify the answer algebraically.

Lesson Plan

Students will be able to

understand the relationship between solutions to linear equations and the graphs of the corresponding functions,
solve by examining where the graph of the linear function crosses the ,
solve by rearranging to get or by examining where the graph of the linear function crosses .

Q1:

The graph in the diagram represents the function . Without performing any calculation, use the graph to solve .

Q2:

The graph in the diagram represents the function . Without performing any calculation, use the graph to solve .

Q3:

Consider the equation . In the following, find a solution by filling the blank space.

These solutions can be plotted as seen in the figure. What will be true of any other solution plotted in the plane?