combining like terms- a mathematical process used to simplify an expression to add or subtract polynomials
constant term- doesn't change when x changes; i.e., 5x-8; 5x+2
system of equations- a set of equations where you want to find a solution that makes all the equations true at the same time; i.e., x+y=5; 2x-y=-2; solution: (1,4)
linear relationship- a relationship between two quantities that graphs a line
slope- rate of change; constant rate;
solution to an equation with two variables- any ordered pair (x,y) that can be used in place of the variables to make the equation true
vertical intercept- the point where the graphed line crosses the vertical axis; "y-intercept"
center (of dilation) - (lesson 3) The point (center) from which a dilation occurs.
dilation - (lesson 2) A dilation occurs when a figure changes size but not shape (shrinks or enlarges) by a scale factor. A dilation must have a center from which the dilation occurs.
scale factor - (lesson 1) The scale factor is the multiplier used to dilate a figure.
similar - (lesson 6) On figure is similar to another if there is a sequence of rigid transformations and dilations that moves the ifrst figure so that it fits exactly over the second.
slope - (lesson 10) The slope of a line is the quotient of the the vertical distance and the horizontal distance between any two points on the line.
alternate interior angles - (lesson 14) Interior angles that are made by a transversal crossing two parallel lines. They are the angles that lie between the parallel lines, not outside them, and are on opposite sides of the transversal.
clockwise - (lesson 2) An object rotating clockwise is turning the same way that the hour or minute hand goes around a clock.
congruent - (lesson 11) One figure is congruent to another if there is a rigid transformation (or a sequence of translations, rotations and reflections) that moves the first figure so that it fits exactly over the second.
corresponding (angles, distances, parts, points, sides) - (lesson 17) Are the image (copy) angles, distances, parts, points or sides of the original shape.
counterclockwise - (lesson 2) An object rotating counterclockwise is turning the opposite way tht the hour or minute hand goes around a clock.
image - (lesson 2) The copy of an original shape.
reflection - (lesson 2) The mirror image (copy) of a figure, always reflected over a "line of reflection".
rigid transformation - (lesson 7) When you move a figure (transform) without changing (rigid) its size or shape. Rotations, reflections and translations are called "rigid transformations" because they move a figure (transform) without changing its size or shape (rigid).
rotation - (lesson 2) When you move a figure in a circular direction. A rotation will always have three elements: direction (clockwise/counterclockwise), distance (measured by degrees) and a center. Example: Triangle A rotated 54g clockwise around center O to get triangle B.
sequence of transformations - (lesson 4) A set of translations, rotations, reflections or dilations that move an original figure in a particular order resulting in a final figure.
straight angle - (lesson 15) Two rays that make an angle that forms a straight line. The angle is called a straight angle, and always equals 180g.
transformation - (lesson 4) A transformation is a translation, rotation, reflection, or dilation or combination of these. Note: Rigid Transformations are only reflections, rotations or translations.
translation - (lesson 2) A translation is when you move a figure by "sliding" up, down, left, right, or diagional. A translation always has direction and distance.
transversal - (lesson 14) A transversal to two parallel lines is a line that cuts across them, intersecting each one.
vertical angles - (lesson 9) a pair of vertical angles is a pair of angles that are across from each other at the point where two lines intersect. They will always be congruent to each other.