Question 108995
Area of a rectangle : {{{A=L*W=76}}}
L=5+4W
Substitute in the area equation.
{{{L*W=76}}}
((((5+4W)*W=76}}}
{{{5W+4W^2=76}}}
{{{4W^2+5W-76=0}}}
Use the quadratic formula,
{{{W = (-b +- sqrt( b^2-4*a*c))/(2*a)}}} 
{{{W = (-5 +- sqrt( 5^2-4*4*(-76) ))/(2*4)}}}
 {{{W = (-5 +- sqrt( 1241 ))/(8)}}}
Since a negative width doesn't make sense, we will only use the positive root.
{{{W = (-5 + sqrt( 1241 ))/(8)}}}
{{{W = (-5 + 35.22783)/(8)}}}
{{{highlight(W=3.778)}}}
{{{L=5+4W}}}
{{{L=5+4*(3.778)}}}
{{{L=5+15.114}}}
{{{highlight(L=20.114)}}}
Verify the area to check your answer.
{{{A=L*W=76}}}
{{{(3.778)(20.114)=76}}}
{{{(75.991)=76}}}
Close enough, true statement.
Good answer.