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Middle School Archive
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3D and higher
Browse Middle School Graphing Equations
Stars indicate particularly interesting answers or
good places to begin browsing.
Selected answers to common questions:
Direct and indirect variation.
Slope, slope-intercept, standard form.
- Plotting Points in the Coordinate Plane [01/16/2004]
What is the coordinate plane and how do I plot points like (4,2) on it?
- Quadrant [03/25/2001]
What is a quadrant?
- Sketching Shortcuts [09/30/2012]
An upperclassman quickly sketches a graph packed with logarithms and absolute values; an underclasswoman marvels at his speed — and seeks shortcuts. Doctor Douglas walks through his routine for plotting curves, and along the way exploits symmetries that conserve effort.
- Slope-Intercept Formula [06/05/2001]
Why does y = mx + b have to be that way?
- Standard Form in Linear Equations [11/21/2001]
Where is standard form used?
- T-Charts and Graphs [11/11/2001]
Make a table of values for the line y = x/4+4 using x-values of 1,2,3,4,
and 5. Which graph shows the line that passes through the ordered pairs
of the table?
- Translation [9/11/1996]
What does translation mean?
- Using X and Y to Represent the Axes [9/29/1995]
Why are the axes on a graph x and y and not any other letter in the
alphabet, and why is the y-axis generally vertical and the x-axis
- Why Y Rises and X Runs [12/19/2012]
A teacher seeks an explanation for why slope is "rise over run" rather than "run over
rise." Doctor Peterson reveals the logic, as well as a way to investigate these kinds of
imponderables, before affirming her derivation from slope-intercept form and
suggesting related motivations from other applications.
- Write in Slope-Intercept Form [11/06/1997]
Write and sketch x - y + 2 = 0 .
- X- and Y-Intercepts [09/15/1998]
I'm having a hard time finding out how to solve an equation and then do
the graph. The intercepts confuse me also...
- X Line in a 3D Graph [03/10/2001]
Which is the x line - vertical or horizontal?
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