Question

Find the area in square metres, of the triangle
whose base and altitude are as under:
(a) base = 22 dm and altitude = 10 dm
(b) base = 65 cm and altitude = 20 cm
(c) base = 10 m and altitude = 70 cm
(d) base = 1200 cm and altitude = 90 dm
please tell me answer ​

Answer 1

Answer:

1 dm = 0.1 m

1 cm = 0.01 m

Area of Triangle = 1/2 × base × altitude

(a) Area = 1/2 × 22 dm × 10 dm

= 1/2 × 2.2 m × 1 m

= 2.2/2 = 1.1 m²

Area = 1.1 m²

(b) Area = 1/2 × 65 cm × 20 cm

= 1/2 × 0.65 m × 0.2 m

= 0.65 × 0.1 = 0.065 m²

Area = 0.065 m²

(c) Area = 1/2 × 10 m × 70 cm

= 1/2 × 10 m × 0.7 m

= 1/2 × 7 = 3.5 m²

Area = 3.5m²

(d) Area = 1/2 × 1200 cm × 90 dm

= 1/2 × 12 m × 9 m

= 6 × 9 = 54 m²

Area = 54 m²