Question 858060
Let 
x      - be the length
x-10   - be the width
x+10   - be the diagonal

If you see, the length of the diagonal is the hypotenuse when you omit one side of the length and the width, it forms a right triangle. :)

So this means,

{{{d^2=l^2+w^2}}}
{{{(x+10)^2=(x-10)^2+x^2}}}
{{{x^2+20x+100=x^2-20x+100+x^2}}}
{{{x^2+20x+100=2x^2-20x+100}}}
{{{-x^2=-40x}}}
{{{x=40}}}

40 in length, 30 inch width and 50 inch is the diagonal!


Hope that helps!!
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