Question

In the given figure, ABCD is a parallelogram. DL is perpendicular to AB and AB = 12 cm. AD = 10 cm. If the area of parallelogram is $72c{m}^2$ then, AL = __

Answer 1

Area of parallelogram $=Base\times correspondingaltitude$

$72=12\times DL$

$DL=6cm$

Apply Pythagoras theorem in Triangle DLA

$A{D}^2=D{L}^2+A{L}^2$

${10}^2=6^2+A{L}^2$

$100=36+A{L}^2$

$A{L}^2=64$

$AL=8cm$