The area of a rectangle in 60 cm2 and its perimeter is 34 cm, then the length of the diagonal is
Let the length and breadth of rectangle be $$l$$ and $$b$$ cm respectively
=> Diagonal = $$d = \sqrt{l^2+b^2}$$ cm
Area of rectangle = $$lb=60$$ ------------(i)
Perimeter of rectangle = $$2(l+b)=34$$
=> $$l+b=\frac{34}{2}=17$$
Squaring both sides,
=> $$(l+b)^2=(17)^2$$
=> $$l^2+b^2+2lb=289$$
=> $$l^2+b^2+2(60)=289$$ Â Â [Using (i)]
=> $$l^2+b^2=289-120=169$$
=> $$\sqrt{l^2+b^2}=\sqrt{169}$$
=> $$d=13$$ cm
=> Ans - (D)
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