Teaching Algebra with Manipulatives

Using Overhead Manipulatives
(Use with Algebra 1, Lesson 4-5)
Graphing Linear Relations
Objective Graphing linear equations on a coordinate plane.
Materials
• coordinate grid transparency*
• transparency pen*
• transparency prepared as described below
three blank transparencies * available in Overhead Manipulative Resources
Demonstration
Graphing Linear Equations
• Prepare a transparency with the table shown at the
right. Do not copy the numbers shown in parentheses
or the heading of the second column.
• Place a blank transparency on the table transparency.
Have students complete the table to find five solutions
for the equation y x 1.
• Have students graph all of the ordered pairs. Ask them
whether the graph appears to be linear. yes Have them
draw a line through the points.
x (x 1) y (x, y )
2 (2 1) (1) (2, 1)
1 (1 1) (0) (1, 0)
0 (0 1) (1) (0, 1)
1 (1 1) (2) (1, 2)
2 (2 1) (3) (2, 3)
y
O
x
• Place a blank transparency on the table transparency. Have
students complete the table to find five solutions for the equation
y 3x. (2, 6), (1, 3), (0, 0), (1, 3), (2, 6)
• Have students graph all of the ordered pairs and draw a line
through the points.
y
O
x
• Place a blank transparency on the table transparency. Write the
equation 3x 4y 6 above the table. Ask students how to solve
this equation for y. Subtract 3x from each side; divide each
side by 4.
• Write 6 3x
in the second column of the table.
4
Continue with activity as above.
O
y
x
Algebra 1—Chapter 4
© Glencoe/McGraw-Hill 87 Teaching Algebra with Manipulatives