Binomials are just two-term algebra concepts, such as x + 1. If you multiply two of them, the first term will end up being x multiplied by itself, creating x². the other part will still have a regular x, and a constant. With the addition of x², the binomial will have three parts and become a trinomial.
ISAIAH LOPEZ
Parenthesis can be used to multiply numbers, even in algebra. If you get two binomials, like (x + 3)(x - 4), it will have to make a trinomial. There are four parts, but there will be two of the same number, so you can add like terms and get three parts. In the example specified earlier, I will use a method that is the best for multiplying binomials. It is called the FOIL method. FOIL stands for first, outer, inner, and last. That is the order you will multiply the terms in. (x + 3)(x - 4) will first be multiplied by the 'x's. The x comes first in both binomials, so you will do x times x, which makes x². Then, do the outer, which is what the 'O' in FOIL stands for. x • -4 which is -4x. Then do the inner, (The "I' in FOIL), which is 3 • x (3x). and finally, the last ('L' in Foil). 3 • -4 = -12. There you have it! Just write it out and add like terms. In our example, it's x² - 4x + 3x - 12. Do you notice how the middle terms are like terms? Add them together. -4x + 3x = -1x, or -x. The final answer is a trinomial, "x² - x - 12".