Maximize
Worked Example
Problem: A farmer has 40 meters of fencing and wants to enclose a rectangular garden along a wall (so only three sides need fencing). What dimensions maximize the area of the garden?
Step 1: Let the width be x meters and the length be y meters. Since one long side is against the wall, the fencing constraint is:
2x+y=40
Step 2: Solve for y and write the area A as a function of x:
A=x⋅y=x(40−2x)=40x−2x2
Step 3: This is a downward-opening parabola. Its maximum occurs at the vertex, where x=−2ab:
x=−2(−2)40=10
Step 4: Find y and the maximum area:
y=40−2(10)=20,A=10×20=200
Answer: The area is maximized at 200 square meters, with width 10 m and length 20 m.
Why It Matters
Maximizing appears throughout real-world decisions: businesses maximize profit, engineers maximize efficiency, and designers maximize strength within material limits. In algebra and calculus, learning to maximize a function teaches you how to analyze its behavior and locate its highest point, which is a foundational skill in optimization.
Common Mistakes
Mistake: Ignoring constraints and finding a value that is not actually achievable.
Correction: Always check that your answer satisfies all given constraints (such as positive dimensions or a budget limit). The maximum of a function without constraints may differ from the maximum within a restricted domain.
Related Terms
- Minimize — The opposite goal: finding the smallest value
- Maximum of a Function — The highest point on a function's graph
- Optimization — The broader field of maximizing or minimizing
- Vertex — Location of a parabola's maximum or minimum

