terms that have the same variables raised to the same exponent. e.g. 3x^{2} and 2x^{2}. 

like terms 
 
distributive property 

adding two numbers and then multiplying by another yields the same result as multiplying each one by the number and then adding the products. i.e. a(b + c) = ab + ac, or (a+b)c = ac + bc. E.g. 2(3 + 5) = 2x3 + 2x5. 
 
multiplicative inverses 

two numbers whose product is 1.

 
factor tree 

a diagram representing a systematic way of determining all the prime factors of a number.

 
frustum 

the region a solid cone or pyramid between the base and a plane parallel to the base. 
 
histogram 

a type of statistical graph that uses bars, where each bar represents a range of values and the data is continuous. 
 
inequality 

a mathematical sentence that includes one of the symbols >, <, or the symbols for greater than or equal to, less than or equal to, or not equal. 
 
centroid 

the point of intersection of the three medians of a triangle.

 
commutative property 

the order of numbers in a calculation does not affect the result. e.g. Addition is commutative since a + b = b + a. E.g. 3 + 5 = 5 + 3. Subtraction is not commutative since 8  2 and 2  8 are not equal. 
 
composite number 

a whole number (integer) that has more than 2 different factors. e.g. 18 has factors 1, 18, 2, 9, 3, 6 so it is composite 
 