Question 730996
d=4w and width = w.<P>
The Pythagorean theorem describes the relationship between the two legs ( a and b) of a right triangle and the hypotenuse (c).  In a rectangle, the length and width are the legs, while the diagonal is the hypotenuse.<P>
Pythagorean Theorem:  {{{a^2 + b^2 = c^2}}} <P>
General Rectangle:  {{{l^2 + w^2 = d^2}}}<P>
This specific rectangle with d = 4w:  {{{l^2 + w^2 = (4w)^2 = 16w^2}}}<P>
Solve for l:  {{{l^2 = 16w^2 - w^2= 15w^2}}}<P>
{{{l=sqrt(15w^2)=w*sqrt(15)}}}
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