Let
x----------> length of rectangle <span> surface
</span>y---------->width of rectangle<span> surface
</span><span>
we know that
x*y=221------------> equation 1
and
y=x+4--------------> equation 2
</span><span>I substitute 2 in 1
</span>x*[x+4]=221--------> x²+4x-221=0
<span>
using a graph tool---------> to calculate the quadratic equation
see the attached figure
the solution is
x=13
y=x+4-------> y=13+7-----> y=17
the answer is
</span>the length of rectangle surface is 13 yd
the width of rectangle surface is 17 yd