ratio A comparison of two numbers by division 4 out of 5 people choose product X 4 out of 5 4 to 5 4:5

equivalent ratios Ratios that name the same comparison

proportion An equation that shows two ratios are equivalent

percent Ratio that compares a number to 100, 20% means 20 per hundred or

mean (also called average) The sum of all the values in a data set divided by the number of data values 90, 85, 88, 82, 85 The mean is 86.

mode Value that occurs most often in a data set 3, 4, 4, 5, 6, 7 Mode is 4 3, 4, 4, 5, 6, 6, 7 Modes are 4 and 6 3, 4, 5, 6, 7, 8 No mode

median The number in the middle of an ordered set of data For an odd number of values 5, 5, 6, 6, 7, 8, 9 Median = 6 For an even number of values, average the two middle numbers. 5, 6, 6, 7, 8, 9 6 Median =

bar graph Graph that uses vertical or horizontal lines to display data

circle graph Way to display data using a circle and non-overlapping sectors

box and whisker plot A way to show how data is distributed by using the median, quartiles, and minimum and maximum values

scatter plot Graph that shows the general relationship between two sets of data

variable letter or symbol used to represent a value that can change a f x y constant value that does not change

expression Mathematical phrase that contains operations, numbers, and/or variables Numerical expression An expression that contains only constants 2 4  Algebraic expression An expression that contains at least one variable 8y 4a + 3b x – n – 7m

coefficient A number multiplied by a variable 2x 2 is the coefficient of x 5a – 4b 5 is the coefficient of a and 4 is the coefficient of b

factor Number or expression that is multiplied by another number or expression to get a product 24 = 4  6 4 and 6 are factors of = 2  2  5 2, 2, and 5 are factors of 20 (a 2 – 4) = (a + 2)(a – 2) (a + 2) and (a – 2) are factors of (a 2 – 4)

exponent Number that indicates how many times a number (base) is to be used as a factor 2 3 = 2  2  2 2 is the base; 3 is the exponent. X 4 = x  x  x  x x is the base; 4 is the exponent. (a + b) 2 = (a + b)(a + b) (a + b) it the base; 2 is the exponent.

like terms Terms with the same variables raised to the same powers Like terms 4x 2 y 3 7x 2 y 3 Not like terms 5m 2 n 3 5m 3 n 2

evaluate Find the value of an expression by substituting numbers for the variables and simplifying Evaluate x + y when x = 3 and y = 6. x + y = = 9

equation Mathematical statement that two expressions are equivalent = x – 8 = 20 3x + 2y = 15

inequality Mathematical statement that contains greater than (>), less than (<), greater than or equal to (≥), less than or equal to (≤), or not equal (≠) 5 > 27 < 10x ≥ 1 n +2 ≤ 15x ≠ 6 x – 2 ≥ y + 3

coordinate plane A plane divided into four regions by a horizontal line called the x-axis and a vertical line called the y-axis

coordinate A number used to identify the location of a point on a number line or coordinate plane On the number line, the coordinate of A is 4. On the coordinate plane, the coordinates of B are (-3, 4).

ordered pair Pair of numbers used to locate a point in the coordinate plane First number, x, indicates number of units left or right Second number, y, indicates number of units up or down On the coordinate plane, the coordinates of B are (-3, 4). -3 means 3 units left 4 means 4 units up

origin On a coordinate plane, the intersection of the x-axis and the y-axis with coordinates (0, 0) x-axis Origin (0, 0) y-axis