Horizontal axis: The x-axis Vertical axis: The y-axis Origin: The point (0, 0) Ordered pair (x, y): First number is across, second is up or down Quadrant I: x positive, y positive (top right) Quadrant II: x negative, y positive (top left) Quadrant III: x negative, y negative (bottom left) Quadrant IV: x positive, y negative (bottom right) Where is (0, 5)?: On the y-axis, 5 units above the origin Where is (−3, 0)?: On the x-axis, 3 units left of the origin Which quadrant is (3, −2)?: IV Which quadrant is (−4, −1)?: III Which quadrant is (−2, 6)?: II Reflect (3, 4) over the x-axis: (3, −4) Reflect (3, 4) over the y-axis: (−3, 4) Reflect (3, 4) through the origin: (−3, −4) Reflect (a, b) over the line y = x: (b, a) Translate (2, 1) by 3 right and 2 up: (5, 3) Rotate (a, b) 90° counterclockwise about the origin: (−b, a) Rotate (a, b) 180° about the origin: (−a, −b) Dilate (2, 3) by scale factor 2 about the origin: (4, 6) Distance from (0, 0) to (3, 4): 5 Distance from (1, 2) to (4, 6): 5 Midpoint of (2, 4) and (6, 8): (4, 6) Midpoint of (−2, 3) and (4, −1): (1, 1) Slope through (0, 0) and (2, 4): 2 Slope through (1, 5) and (3, 1): −2 Slope of y = 3x + 2: 3 Y-intercept of y = 3x + 2: 2 X-intercept of y = 2x − 6: 3 Graph of y = 5: A horizontal line Graph of x = −2: A vertical line Graph of y = x: A line through the origin with slope 1 Graph of y = x²: A parabola opening up with vertex at the origin Graph of y = −x²: A parabola opening down Graph of y = |x|: A V shape with vertex at the origin Graph of y = 1/x: A hyperbola with branches in quadrants I and III Graph of y = √x: Half of a sideways parabola starting at the origin Graph of y = 2ˣ: A curve that rises quickly and passes through (0, 1) Graph of x² + y² = 9: A circle with center (0, 0) and radius 3 Shift y = f(x) up 3: y = f(x) + 3 Shift y = f(x) right 2: y = f(x − 2) Reflect y = f(x) over the x-axis: y = −f(x) Reflect y = f(x) over the y-axis: y = f(−x) Stretch y = f(x) vertically by 3: y = 3f(x) Vertex of y = (x − 2)² + 5: (2, 5) Axis of symmetry of y = (x − 2)² + 5: x = 2 Parallel to y = 2x + 1: Any line with slope 2 Perpendicular to y = 2x + 1: Any line with slope −1/2 Rise over run: Slope Positive slope: The line goes up from left to right Negative slope: The line goes down from left to right Where lines of a system meet: The solution of the system Line graph: Plots points joined by lines to show change over time Scale of a graph: The value each grid mark stands for Interval of an axis: The step between marked numbers Latitude and longitude: A coordinate system for locations on Earth Battleship grid: A game that uses coordinates like B7 Plotting order: Start at the origin, move across x, then up or down y René Descartes: Introduced the Cartesian coordinate system Polar coordinates (r, θ): Distance from the origin and angle from the positive x-axis 3D coordinates: Add a z-axis: (x, y, z) Number of axes in a 3D grid: 3 Free flashcards from Peabody at peabody.kids/flashcards/math-coordinate-graphing