Question

Find the area of the triangle in which

(i) base = 42 cm and height = 25 cm,
(ii) base = 16.8 m and height = 75 cm,
(iii) base = 8 dm and height = 35 cm,

Answer 1

We know:
Area of a triangle = $\frac{1}{2}\times \mathrm{Base}\times \mathrm{Height}$
(i) Base = 42 cm
Height = 25 cm
∴ Area of the triangle = $\left(\frac{1}{2}\times 42\times 25\right)$ cm² = 525 cm²
(ii) Base = 16.8 m
Height = 75 cm = 0.75 m [since 100 cm = 1 m]
∴ Area of the triangle = $\left(\frac{1}{2}\times 16.8\times 0.75\right)$ m² = 6.3 m²
(iii) Base = 8 dm = (8 $\times$ 10) cm = 80 cm [since 1 dm = 10 cm]
Height = 35 cm
∴ Area of the triangle = $\left(\frac{1}{2}\times 80\times 35\right)$ cm² = 1400 cm²