When you are multiplying two binomials use FOIL. FOIL stands for First Outer Inner Last When you multiply two binomials you generally end up with three terms. When you multiply a binomial and a trinomial you will generally end up with four terms. Always add like terms to simplify your answer. Practice problems Page all, 22-38all
When you are multiplying items that are squared, write the item twice then FOIL it. If you are squaring differences (ie (x -2)(x +2)) then square the first term, put in a subtraction sign, then square the second term. Practice problems Page all, 15-20all, 28-39all, all
When you are factoring a trinomial you have to follow several steps. First draw an X on your paper. The top part of your X put the product of “a” times “c”. The bottom part of your X put the value of “b”. You then have to think of two numbers whose product equals the top and sums equals the bottom. Replace those two numbers for the one number in the original expression. Put the first two terms together and the other two terms together. Figure out what the first two terms have in common and factor it out and write that parenthesis down twice. Then figure out what you have to multiply it by to come out with your original numbers. Write down the parenthesis you wrote down twice and the outsider. Practice problems Page all, 43-54all
Do these problems the same way you do the problems in 9.5 The only difference is that the product of “a” times “c” will be a bigger number. Practice problems Page all, 33-41all