Solve systems of linear equations by graphing - with some real-life applications

9 teachers like this lesson

Print Lesson

Objective

SWBAT solve real-life systems of linear equations by graphing.

Big Idea

Systems of linear equations can be used to solve real-life problems!

Lesson Author

Jeff Li MTP

New York, NY

Grade Level

Eighth grade

Subjects

Math

Systems of Equations and Inequalities

Algebra

Graphing (Algebra)

Standards

8.EE.C.8

Analyze and solve pairs of simultaneous linear equations.

8.EE.C.8a

Understand that solutions to a system of two linear equations in two variables correspond to points of intersection of their graphs, because points of intersection satisfy both equations simultaneously.

8.EE.C.8b

Solve systems of two linear equations in two variables algebraically, and estimate solutions by graphing the equations. Solve simple cases by inspection. For example, 3x + 2y = 5 and 3x + 2y = 6 have no solution because 3x + 2y cannot simultaneously be 5 and 6.

8.EE.C.8c

Solve real-world and mathematical problems leading to two linear equations in two variables. For example, given coordinates for two pairs of points, determine whether the line through the first pair of points intersects the line through the second pair.

MP1

Make sense of problems and persevere in solving them.

MP2

Reason abstractly and quantitatively.

MP4

Model with mathematics.

MP6

Attend to precision.

Warm-up

10 minutes

Each day, students complete a warm-up that usually consists of spiraling the previous day's material, in addition to older material. Today's Warm-up problems (WU61) also extend the goals of yesterday's lesson.

For a video narrative about how I structure each lesson, and how the warm-up fits in, click here.

A quick note - today's BRONZE problems are from Coach New York Grade 8.

Play of the Day

40 minutes

Leading with the application of real-life systems

6 - 2 student work sample GOLD 1.pdf

6 - 2 student work sampler GOLD 2.pdf

Huddle

10 minutes

Homework

15 minutes

HW61 Solve real-life systems of linear functions by graphing includes four problems related to this lesson. I also give the kids the answers to the problems at the end of the assignment.

Previous Lesson

Next Lesson

Algebra I » Systems of Linear Equations