 | Lesson Objective: Students will roll three dice with the calculator
and keep a chart of their rolls to discover which combination of numbers will
form a triangle.
|
| Materials needed: 1 TI-73 for each pair of
students
Straws
Tape
Scissors
Poster Paper
|
| Procedure: Show students how to
roll
three dice using the TI-73. |
| Pair students to work together on the next task. |
| Distribute 1 calculator per pair of students. Distribute large sheet of
poster paper, piece of paper, tape, and about 24 straws. |
| Give directions to generating three numbers on a die: Math Prb, 7 dice (3) |
| After students understand the operation of the calculator distribute
material for students to make triangle and show the students how the triangles
will be formed with the ties and straws. Remind students to be very accurate
with their cutting so they can make good conjectures. |
| Students will roll the dice, try to build the triangle, and then record
their results in a chart. |
| As students build the triangles with the straws have them attach them to a
sheet of paper and label the lengths of the sides clearly with large numbers.
|
| Students should display all examples:
| some will produce triangles |
| some will produce three line segments where the two smaller sides
exactly total the third side |
| some will produce three line segments where the two smaller sides
total much less than the third side. |
Each group of students will complete 10 trials. They should record their
three measurements, try to build the triangle, and see which pair of students
is able to create more triangles.
Students will look to see if they can make a conclusion about which set of
numbers make a triangle.
Follow up activities
 | After students have had time to collect 10 trials make a list of all the
triangles the students have found that make a triangle. Record them on
a class list. Have students look for a way to generalize what the
class chart tells them about the relationship of the three numbers that form
a triangle. |
| The students will try to give a new set of numbers that makes a triangle
and explain why the three numbers makes a triangle. |
| The students will try to give a new set of numbers that won’t make a
triangle and explain why the three numbers does not make a triangle. |
Extensions:
| Have students look at their triangles and classify the triangles by the
type of triangles formed. How many are right triangle? How many
are acute triangles? How many are obtuse triangles? How many are
equilateral? How many are isosceles? How many are scalene?
|
| Make some observations about some of the triangles. Look for
relationships between a2 , b2 and c2 when
the triangle is a right triangle, an acute triangle, and an obtuse triangle. |
|
