Question

Mark (✓) against the correct answer in each of the following:
In a ||gm ABCD, DL ​⊥ AB and BM ​⊥ AD. If AB = 10 cm, DL = 6 cm and BM = 8 cm, then AD = ?
(a) 8 cm
(b) 9 cm
(c) 7 cm
(d) 7.5 cm

Answer 1

(d) 7.5 cm
Area of a parallelogram = Base $\times$Height
Area of parallelogram ABCD = AB $\times$DL
$\Rightarrow$ AD$\times$MB = AB $\times$DL
$\Rightarrow$ AD$\times$8 = 10$\times$6
$\Rightarrow$ AD$\times$8 = 60
$\Rightarrow$AD = 7.5 cm