If the length of a rectangle is increased by 7 units and the breadth is decreased by 3 units, its area does
not change. If the length of the rectangle is decreased by 7 m and breadth is increased by 5 m, are
remains unaffected. Find the length and breadth of the rectangle.
Answers
Answer:
The area of a rectangle remains the same if the lengthis increased by 7 metres and the breadth is decreased by 3 meters. The area remains unaffected if the length isdecreases by 7 metres andbreadth is increased by 5metres.
Step-by-step explanation:
Let the length of the rectangle be x metres and the breadth be y metres.
Area of the rectangle=length×breadth
=x×y=xy sq. metres
From the given information, we have,
(x+7)×(y−3)=xy
and(x−7)×(y+5)=xy
(x+7)×(y−3)=xy
=>xy−3x+7y−21=xy
=>−3x+7y−21=0
=>7y=3x+21....(i)
Also,(x−7)×(y+5)=xy
=>xy+5x−7y−35=xy
=>5x−7y−35=0....(ii)
Substituting equation (i) in equation (ii), we get,
5x−7y−35=0
=>5x−3x−21−35=0
=>2x=56
=>x=28
Substituting x=28 in equation (i), we get,
7y=3x+21
=>7y=3(28)+21
=>7y=105
=>y=
7
105
Therefore, length of rectangle =x=23 metres
and breadth of rectangle =y=15 metres