Look at the pattern.
- What is the perimeter of Figure 7?
- What is the area of Figure 9?
- What is the perimeter of Figure 9?
(a)
Figure perimeter:
Figure 1 = 8 x 2 = 16 cm
Figure 2 = 8 x 3 = 24 cm
Figure 3 = 8 x 4 = 32 cm
Figure 4 = 8 x 5 = 40 cm
Formula:
Perimeter = 8 x (Figure Number + 1)
Perimeter of Figure 7
= 8 x (7 + 1)
= 8 x 8
= 64 cm
(b)
Figure Area:
Figure 1 = 1 x 16 = 16 cm
2 Figure 2 = 2 x 16 = 32 cm
2 Figure 3 = 3 x 16 = 48 cm
2 Figure 4 = 4 x 16 = 64 cm
2 Area of Figure 9
= 9 x 16
= 144 cm
2 (c)
Perimeter of Figure 9
= 8 x (9 + 1)
= 8 x 10
= 80 cm
Answer(s): (a) 64 cm; (b) 144 cm
2; (c) 80 cm