Science, Tech, Math › Math Definition and Examples of Binomials in Algebra Share Flipboard Email Print Tetra Images / Getty Images Science, Tech, Math Math Tutorials Geometry Arithmetic Pre Algebra & Algebra Statistics Exponential Decay Functions Worksheets By Grade Resources View More By Deb Russell Math Expert Deb Russell is a school principal and teacher with over 25 years of experience teaching mathematics at all levels. our editorial process Deb Russell Updated January 19, 2019 A polynomial equation with two terms usually joined by a plus or minus sign is called a binomial. Binomials are used in algebra. Polynomials with one term will be called a monomial and could look like 7x. A polynomial with two terms is called a binomial; it could look like 3x + 9. It is easy to remember binomials as bi means 2 and a binomial will have 2 terms. A classic example is the following: 3x + 4 is a binomial and is also a polynomial, 2a(a+b) 2 is also a binomial (a and b are the binomial factors). The above are both binomials. When multiplying binomials, you'll come across a term called the FOIL method which is often just the method used to multiply binomials. For instance, to find the product of 2 binomials, you'll add the products of the First terms, the Outer terms, the Inner terms, and the Last terms. When you're asked to square a binomial, it simply means to multiply it by itself. The square of a binomial will be a trinomial. The product of two binomials will be a trinomial. Example of Multiplying Binomials (5 + 4x) x (3 + 2x)(5 + 4x)(3 + 2x)= (5)(3) + (5)(2x) + (4x)(3) + (4x)(2i)= 15 + 10x + 12x + 8(x)2 = 15 + 22x + 8(-1)= 15 + 22x - 8 = (15 - 8) + 22x = 7 + 22x Once you begin taking algebra in school, you'll be doing a great many computations that require binomials and polynomials.