A person has 20 M of fencing to build a chicken run for their chickens. The side of their barn is also a side of their chicken run. What is the largest area the chicken run can be if it must be rectangular?
How to solve this question?
I literally have no clue on how to solve this question. I have tried to make an equation like 2y+x=20 but it doesn't get me anywhere.
I thank you in advance for helping me
HINT: Leaving out one side of barn
$$ 2 B +L = 20 $$
Maximize $$ A = L * B$$
After plugging in from first equation to eliminate L,
$$ A= B( 20-2B) $$
Result will be when $ L=10, B=5 ,$ with vanishing derivative w.r.to B for maximum area.