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Question
The length of a rectangle is twice its width. If its perimeter is 30 units, find its dimensions.
Solution
Let the length and breadth of a rectangle be x units and y units respectively.
According to given information, we have
x = 2y
⇒ x - 2y = 0 ....(i)
ALso, perimeter of a rectangle = 30 units
⇒ 2(x + y) = 30
⇒ x - y = 15 ....(ii)
Subtracting eqn. (ii) from eqn. (i), we get
-3y = -15
⇒ y = 5
Substituting the value of y in eqn. (1), we get
x - 2(5) = 0
⇒ x - 10 = 0
⇒ x = 10
Thus, the length and breadth of a reactangle are 10 units and 5 units respectively.
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