• Coefficient: A number used to multiply a variable. Example: 6z means 6 times z, and "z" is a variable, so 6 is a coefficient.

• Equation: An equation is a statement about equality between two expressions. If the expression on the left side of the equal sign has the same value as the expression on the right side of the equal sign, then you have a true equation.

• Like Terms: Terms whose variables and their exponents are the same. Example: 7x and 2x are like terms because the variables are both “x”. But 7x and 7 are NOT like terms because the x’s don’t have the same exponent.

• Linear Expression: An expression that contains a variable raised to the first power

• Solution: A solution of a linear equation in is a number, such that when all instances of are replaced with the number, the left side will equal the right side.

• Term: In Algebra a term is either a single number or variable, or numbers and variables multiplied together. Terms are separated by + or − signs

• Unit Rate: A unit rate describes how many units of the first type of quantity correspond to one unit of the second type of quantity. Some common unit rates are miles per hour, cost per item & earnings per week Variable: A symbol for a number we don't know yet. It is usually a letter like x or y. Example: in x + 2 = 6, x is the variable.

• Horizontal Line: In a Cartesian plane, a horizontal line is either the -axis or any other line parallel to the -axis.

• Linear Equation: An equation in which both expressions are linear expressions.

• Point-Slope Equation of a Line: In point-slope form, y1 is the y value of the known point on the line, m is the slope and x1 is the x value of the known point.

• Slope of a Line in a Cartesian Plane: Slope is a number that can be used to describe the steepness of a line in a coordinate plane. The slope of a line is often represented by the symbol .

• Slope-Intercept Equation of a Line: When the equation is written as y = mx + b. The slope is the number "m" that is multiplied on the x, and "b" is the y-intercept, where the line crosses the y-axis.

• Solution to a System of Linear Equations: A solution to a system of two linear equations in two variables is an ordered pair of numbers that is a solution to both equations

• System of Linear Equations: A system of linear equations is a set of two or more linear equations.

• Vertical Line: In a Cartesian plane, a vertical line is either the -axis or any other line parallel to the -axis.

• X-Intercept: An -intercept of a graph is the -coordinate of a point where the graph intersects the -axis. An -intercept point is the coordinate point where the graph intersects the -axis.

• Y-Intercept: A -intercept of a graph is the -coordinate of a point where the graph intersects the - axis. A -intercept point is the coordinate point where the graph intersects the -axis.

Vocabulary

The constant of proportionality- can be thought of as the rate of change of one variable with respect to the other.

Linear Relationship- A relationship between two quantities in where there is constant variation between the two quantities.

Rise- The vertical change from one point to a second point on a coordinate plane.

Run- The horizontal change from one point to a second point on a coordinate plane.

Slope- The Ratio of the rise, or vertical change, to the run, or horizontal change, between any two points on a nonvertical line on the coordinate plane.

Slope-intercept form- A form of a linear equation, y = mx + b, where m is the slope and be is the y-intercept of the graph of the equation.

Y-intercept- The point on a coordinate plane where the graph of a line crosses the y axis.

X-intercept- The point on a coordinate plane where the graph of a line crosses the x axis.

Positive Slope- A line with positive vertical change from left to right.

Ordered Pairs- Two coordinates used to graph a point on a coordinate plane. Written as (x,y) where the first number indicates the distance on the x axis and the second the distance on the y axis.

Negative Slope- A line with negative vertical change from left to right.

No Slope- A line which is flat--having no vertical change from left to right.

Undefined Slope- A line which is vertical, straight up and down, has an undefined slope because its vertical change is divided by zero (no horizontal change).

Determining Direct Proportion A Direct Proportion:

1. Passes through (0,0)

2. Has a consistent slope (AKA K or Constant value, also written as "m" in slope-intercept form)

3. K can be found by putting in (1,y) and finding the y value over 1.

• clockwise-Clockwise means to turn in the same direction as the hands of a clock. The top turns to the right.

• counterclockwise-Counterclockwise means to turn opposite of the way the hands of a clock turn. The top turns to the left.

• reflection-A reflection across a line moves every point on a figure to a point directly on the opposite side of the line. The new point is the same distance from the line as it was in the original figure.

• rotation-A rotation moves every point on a figure around a center by a given angle in a specific direction.

• translation-A translation moves every point in a figure a given distance in a given direction.

• vertex-A vertex is a point where two or more edges meet. When we have more than one vertex, we call them vertices.

• Corresponding Angles- If two parallel lines are cut by a transversal, then the pairs of corresponding angles are congruent.

• Corresponding Angles Converse- If two lines are cut by a transversal and the corresponding angles are congruent, the lines are parallel.

• Alternate Interior Angles-If two parallel lines are cut by a transversal, then the alternate interior angles are congruent.

• Alternate Exterior Angles- If two parallel lines are cut by a transversal, then the alternate exterior angles are congruent.

• Interiors on Same Side If two parallel lines are cut by a transversal, the interior angles on the same side of the transversal are supplementary.

• Alternate Interior Angles Converse- If two lines are cut by a transversal and the alternate interior angles are congruent, the lines are parallel.

• Alternate Exterior Angles Converse- If two lines are cut by a transversal and the alternate exterior angles are congruent, the lines are parallel.

• Interiors on Same Side Converse- If two lines are cut by a transversal and the interior angles on the same side of the transversal are supplementary, the lines are parallel.