Question

Fill in the blanks.

(i) If d₁ and d₂ be the diagonals of a rhombus, then its are is (......) sq units.
(ii) If l,b and h be the length, breadth and height respectively of a room, then area of its 4 walls = (......) sq units.
(iii) 1 hectare = (......) m².
(iv) 1 are = ......m².
(v) If each side of a triangle is a cm, then its area = ...... cm².

Answer 1

(i) If d₁ and d₂ be the diagonals of a rhombus, then its area is $\left(\frac{1}{2}{d}_1{d}_2\right)$ sq. units.
Area of a rhombus = $\frac{1}{2}$× (Product of its diagonals)

(ii) If l, b and h are the length, breadth and height respectively of a room, then area of its 4 walls = 2h(l + b) sq. units.

(iii) 1 hectare = (10000) m²
(since 1 hectometre = 100 m)
∴1 hectare = (100 × 100) m²
(iv) 1 acre = 100 m²
(v) If each side of a triangle is a cm, then its area = $\frac{\sqrt{3}}{4}{a}^2$ cm².
Area of equilateral triangle with side a = $\left(\frac{\sqrt{3}}{4}{a}^2\right)$sq. units.