Question 105103
First, let as assume.
Let x = the width of the plot
x + 10 = length of the plot

Then the area is x(x + 10)
Since it is stated in the problem that the area is 875 square feet, our final equation will be:
{{{x (x + 10) = 875}}}
Solve it:
{{{x (x + 10) = 875}}}
{{{x^2 + 10x = 875}}}
{{{x^2 + 10x + -875 = 0}}}
Applying the quadratic formula
{{{x = (-b +- sqrt( b^2-4*a*c ))/(2*a) }}} 
{{{x = (-(10) +- sqrt( 10^2-4*1*(-875)))/(2*1)}}}
{{{x = (-10 +- sqrt( 100-(-3500)))/2}}}
{{{x = (-10 +- sqrt(3600))/2}}}
{{{x = (-10 +- 60)/2}}}

Now we can solve for the two roots
{{{x = (-10 + 60)/2}}} or {{{x = (-10 - 60)/2}}}
{{{x = (50)/2}}} or {{{x = (-70)/2}}}
{{{x = 25}}} or {{{x = -35}}}

But since we are looking for a real positive number, let us take {{{x = 25}}} as our answer. Therefore, the width is 25 ft and the length is 35 ft.

Thank you. ~kmcruz09~