Linear Inequalities
http://www.maa.org/taxonomy/term/40359/0
enDogs Don't Need Calculus
http://www.maa.org/programs/faculty-and-departments/classroom-capsules-and-notes/dogs-dont-need-calculus
<div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p><em>The authors use inequalities to solve optimization problems without resorting to calculus, as illustrated by four common examples in calculus.</em></p>
</div></div></div>Proof Without Words: Harmonic Mean < Geometric Mean < Arithmetic Mean ...
http://www.maa.org/programs/faculty-and-departments/classroom-capsules-and-notes/proof-without-words-harmonic-mean-geometric-mean-arithmetic-mean
<div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p><em>The author proves visually four chain inequalities among five common means: harmonic, geometric, arithmetic, root square, and contraharmonic.</em></p>
</div></div></div>The Coffee Shop - Linear Inequalities
http://www.maa.org/programs/faculty-and-departments/course-communities/the-coffee-shop-linear-inequalities
Lesson 43: Linear Inequalities in Two Variables
http://www.maa.org/programs/faculty-and-departments/course-communities/lesson-43-linear-inequalities-in-two-variables