A square lawn is surrounded by a path 2 m wide. If the area of
the path is 240 m², find the area of the lawn
Answers
Length of outer side = (a + 2 + 2) = (a + 4) m. Area of outer side = (a + 4)² = a² + 8a + 16. Also given, Area of path is 240 m².
Answer
Let the side of lawn be 'a' m.
Let the side of lawn be 'a' m.Area of lawn = a2
Let the side of lawn be 'a' m.Area of lawn = a2Length of outer side =(a+4) m
Let the side of lawn be 'a' m.Area of lawn = a2Length of outer side =(a+4) mArea of outer square=(a+4)2
Let the side of lawn be 'a' m.Area of lawn = a2Length of outer side =(a+4) mArea of outer square=(a+4)2= a2+8a+16
Let the side of lawn be 'a' m.Area of lawn = a2Length of outer side =(a+4) mArea of outer square=(a+4)2= a2+8a+16Area of the path = Area of outer sqare-Area of low
Let the side of lawn be 'a' m.Area of lawn = a2Length of outer side =(a+4) mArea of outer square=(a+4)2= a2+8a+16Area of the path = Area of outer sqare-Area of low⇒240=a2+8a+16−a2
Let the side of lawn be 'a' m.Area of lawn = a2Length of outer side =(a+4) mArea of outer square=(a+4)2= a2+8a+16Area of the path = Area of outer sqare-Area of low⇒240=a2+8a+16−a2⇒240=8a+16
Let the side of lawn be 'a' m.Area of lawn = a2Length of outer side =(a+4) mArea of outer square=(a+4)2= a2+8a+16Area of the path = Area of outer sqare-Area of low⇒240=a2+8a+16−a2⇒240=8a+16⇒8(a+2)=240
Let the side of lawn be 'a' m.Area of lawn = a2Length of outer side =(a+4) mArea of outer square=(a+4)2= a2+8a+16Area of the path = Area of outer sqare-Area of low⇒240=a2+8a+16−a2⇒240=8a+16⇒8(a+2)=240⇒a+2=8240
⇒a+2=30
⇒a+2=30⇒a=30−2
⇒a+2=30⇒a=30−2⇒a=28
⇒a+2=30⇒a=30−2⇒a=28side of lawn =30 m
⇒a+2=30⇒a=30−2⇒a=28side of lawn =30 mArea of lawn = 28×28
⇒a+2=30⇒a=30−2⇒a=28side of lawn =30 mArea of lawn = 28×28 = 784 m2