Question 877210
 
 
Let Width = w
Let Length = w+7

{{{w*(w+7)=260}}} Because l*w = A
{{{w^2+7w-260=0}}}
{{{x = (-b +- sqrt( b^2-4*a*c ))/(2*a) }}}
{{{x = (-7 +- sqrt( 7^2-4*1*-260 ))/(2*1) }}}
{{{x=(-7+-sqrt(49+1040))/2}}}
{{{x=(-7+-sqrt(1089))/2}}}
The square root of 1089 is 33. Because both dimensions must be positive,
{{{x=(-7+33)/2}}}
{{{x=26/2}}}
x=13
The width is 13cm and the length is 20cm.