A rectangular mat has an area of 120 sq.metres and perimeter of 46 m. The length of its diagonal is:  Choose the correct choice from the following choices.
A) 19m
B) 17m
C) 15m
D) 16m
E) 20m
rectangular area = l × b = 120 and perimeter = 2(l+b) = 46   l+b = 23   (l-b)power2 - 4lb = (23)power2 - 4 × 120 = (529-480)= 
<gadget id="calculator">(529-480)</gadget>
<output>49</output>
49= l-b = 7   l+b = 23, l-b = 7, we get l = 15, b = 8   Diagonal = √152+82   √ 225+64= 
<gadget id="calculator"> 225+64</gadget>
<output>289</output>
&gt; √289= 17m   Answer is 17m.
<result>B</result>
A rectangular mat has an area of 120 sq.metres and perimeter of 46 m. The length of its diagonal is: