How to solve a problem when asked to switch the digits of a 2-digit number.
How to recognize and factor a binomial that is the difference of perfect squares.
How to recognize special products of polynomials.
How to factor perfect square trinomials.
How to find additive and multiplicative inverses.
How to solve word problems when mixing two quantities with different prices.
How to solve word problems about mixing two liquids with different percent concentrations.