Concept Byte: Solving Systems Using Tables and Graphs

Use With Lesson 6-1

TECHNOLOGY

Activity

Solve the system using a table.

y = 3 x − 7 y equals 3 x minus 7

y = − 0.5 x + 7 y equals negative 0.5 x plus 7

• Step 1 Enter the equations in the y = begin box , y equals , end box  screen.

  

• Step 2 Use the tblset begin box , tblset , end box  function. Set TblStart to 0 and Δ Tbl cap delta cap tbl  to 1.

  

• Step 3 Press table begin box , table , end box  to show the table on the screen.

  

1. Which x-value gives the same value for Y 1 cap y sub 1 and Y 2 cap y sub 2 ?
2. What ordered pair is the solution of the system?

Activity

Solve the system using a graph.

y = − 5 x + 6 y equals negative 5 x plus 6

y = − x − 2 y equals negative x minus 2

• Step 1 Enter the equations in the y = begin box , y equals , end box  screen.
• Step 2 Graph the equations. Use a standard graphing window.
• Step 3 Use the calc begin box , calc , end box  feature. Choose INTERSECT to find the point where the lines intersect.

3. Copy and complete: The lines intersect at (___?___, ___?___), so this point is the solution of the system.

Exercises

Use a table and a graph to solve each system. Sketch your graph.

4. y = 5 x − 3 y equals 5 x minus 3

   y = 3 x + 1 y equals 3 x plus 1

5. y = 2 x − 13 y equals 2 x minus 13

   y = x − 9 y equals x minus 9

6. 2 x − y = 1.5 2 x minus y equals 1.5

   y = − 1 2 x − 1.5 y equals negative , 1 half , x minus 1.5

Table of Contents