The diagonal of a rectangle is 41 cm and its area is 20 sq. cm. The perimeter of the rectangle must be:  Choose the most appropriate option:	A) 18	B) 19	C) 20	D) 21	E) 46
l2 + b2 = 41.   Also, lb = 20.   (l + b)2 = (l2 + b2) + 2lb = 41 + 40= 
<gadget id="calculator">41 + 40</gadget>
<output>81</output>
81   (l + b)= 9.   Perimeter = 2(l + b) = 18 cm.   18nswer:18
<result>A</result>
The diagonal of a rectangle is 41 cm and its area is 20 sq. cm. The perimeter of the rectangle must be: