1. Area of Triangles

2. Formula To find the area for a triangle, the formula is: ½ x B x H
Remember that ½ can be entered into the calculator as 0.5 (like ½ of a dollar is 0.50 cents)

3. Example In this triangle: B= 6 in. H= 8 in.
Let’s plug it into our formula:
½ x B x H =
0.5 x 6 x 8 =
24 inches squared
8 in
6 in

4. Try Another In this triangle: B= 24 H= 7
Let’s plug this into our formula:
½ x B x H =
0.5 x 24 x 7 =
84 cm squared
7 cm
24 cm

5. Your Turn In this triangle: B= 36 H= 12
Let’s plug this into our formula:
½ x B x H =
0.5 x 36 x 12 =
216 mm squared
12 mm
36 mm

6. Perimeter and Area Review

7. Find the Perimeter and Area
L x W=
5 x 3 = 15 in squared

8. Find the Perimeter and Area
8 cm
8 cm
6 cm
14 cm
Perimeter=
8+8+14= 30 cm
Area=
½ x B x H =
0.5 x 14 x 6=
42 cm squared

9. Find Perimeter and Area
24 mm
Perimeter=
= 96 mm
Area=
L x W =
24 x 24 = 576 mm squared

10. Find the Perimeter and Area
L x W =
8 x 4 = 32 in squared

11. Independent Practice
Complete the independent Practice Sheet finding the Perimeter and Area of all the shapes.
Remember, this is your work…there is no talking!