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Browse High School Equations, Graphs, Translations
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Selected answers to common questions:
Direct and indirect variation.
Slope, slope-intercept, standard form.
- Equation of a Rectangle? [11/11/2012]
A student wonders if there is an equation for a rectangle in the Cartesian plane,
comparable to the one for the equation of a circle. Doctor Peterson confirms the student's
suspicions about the difficulties involved.
- Equation of a Sphere [7/3/1995]
What is the equation for a sphere on a graph with the dimensions x,
y, and z?
- Equation of Parabola with Given Vertex, Point [8/4/1996]
How do I find the equations for all parabolas containing the origin whose
vertex is at (2,1)?
- Equations that Meet on a Graph [03/09/2002]
Graph d = 30t and d = 28t+12 (d is distance and t is time).
- Equations with Two Variables [03/25/1998]
Identify and find solutions to systems of equations or inequalities by
- Evaluating Composite Functions [1/31/1996]
If f(x) = 3, and g(x) = x^2 + 1 divided by the square root of (x^2 -1),
how do you evaluate the composite function of f composed with g (f circle
- Finding a Point Equidistant From Two Other Points [8/18/1996]
Point A is (-5,-3), and point B is (-1,-5); to be equidistant from A and
B, what should the value of k be for the point (3,k)?
- Finding a Point on a Circle [5/28/1996]
How do I find the y1 value?
- Finding Asymptotes [07/06/1998]
In the equation y = (m/x) + c, how do the values of m and c affect the
graph? How do you find the asymptotes?
- Finding Equations of Parabolas [12/12/1996]
Determine the equation of the parabola whose vertex is at (1,3) and whose
directrix is y=x.
- Finding Focus and Directrix [04/12/2001]
How can you find the focus and directrix when given a formula for a
- Finding Intervals in Trig Graphs [10/25/1998]
Can you help me with graphing sine and cosine functions? How do you mark
off the intervals?
- Finding Point of Intersection [05/08/2001]
Is there a formula to tell if two lines, given by point coordinates,
cross and at what coordinates they cross?
- Finding the Center of a Circle [06/06/1999]
How can I find the center and radius of a circle that is in the form:
Ax^2 + Cy^2 + Dx + Ey + F = 0?
- Finding the Equation of a Curve [10/02/2000]
I'm looking for an equation for a curve that describes the way people
store information about pending events over time. I would also like to
know how to find the equation of any curve.
- Finding the Equation of a Line [01/08/1997]
Given either a point and a slope or two points, how do you find the
equation of a line in both point-slope and standard form?
- Finding the Equation of a Parabola [04/28/2001]
How can I find the equation of a parabola whose zeros are at 0 and 6, and
whose minimum value is -9?
- Finding the Equations of Two Circles [9/30/1995]
Find the equation of the circles with the center at (4,-7) and touching
(externally and internally) the circle with the equation: (X^2)+(Y^2)+4X-
- Finding the Table's Diameter [05/05/2001]
A circular table is pushed into the corner of a room so that it touches
both walls. On the edge of the table is a scratch 8" from one wall and 9"
from the other wall. What is the diameter of the table?
- Finding the Zeros of a Function [05/12/1999]
How would I find the zeros of P(x) = (x^2-3)(2x-7)^2(x-1)^3, and what is
meant by "state the multiplicity of each"?
- Finding Three Lines that Form a Triangle [08/30/2001]
Find an equation for each of the lines that goes through the point (3,2)
forming a triangle of area 12 with the coordinate axes.
- First Principle Hyperbolas [01/05/1999]
How do you solve for the standard equation of a hyperbola given its
- Folium of Descartes and Parametric Equations [11/23/1998]
How do you plot an implicit function, such as the folium of Descartes,
with the equation y^3 + x^3 = 3xy?
- Formula for a Helix [07/08/1997]
What is the formula that gives the height above the ground of a point on
- Functions Possible for a Symmetric, Asymptotic Graph [02/02/2013]
A student seeks an even function that would represent a graph with a horizontal
asymptote and symmetry around the y-axis. Doctor Peterson suggests considering
functions of the form 1/f(x) — or graphing f(x) by finding 1/y for every x.
- The General Polynomial Function [09/17/1998]
How do you relate a polynomial like y=6x-2 to the general polynomial
function? How do I graph and find the inverse of y=sqrt(2)?
- Generating Fractal Equations [7/1/1996]
Is there any way to generate a fractal equation from a set of numbers?
- Given n Points, find a Polynomial Function... [6/27/1996]
Find a polynomial F(x) of degree less than n so that the graph of F
passes through all of the points.
- Graphing Absolute Values [07/03/2002]
I have a function, f(x), that I can graph, but I don't understand how
to graph |f(x)|.
- Graphing a Circle [04/14/1998]
I would like to know how to graph the equation of a circle.
- Graphing a Function with Asymptotes [07/05/1998]
How do you find the asymptotes of f(x) = (2x + 1)/(x - 3)? How do you use
the asymptotes to graph the function?
- Graphing a Line Given a Point on It and Its Slope [03/07/2004]
I am completely confused about how to graph lines. The question is
asking me to graph the line that goes through the point (0,2) with a
slope m = 1/4. I am not sure what slope m = 1/4 means.
- Graphing and Understanding Conic Equations [12/11/1995]
How can I sketch and find the vertices of this conic equation?
- Graphing an Ellipse [11/20/1998]
How do you graph an ellipse? What is the equation?
- Graphing an Equation [11/08/1997]
Please explain how to graph this equation: y = a + b(x) + c(x^2) + ...
- Graphing a Parabola [4/3/1995]
How do you graph the quadratic equation, y=3(x+1)^2 -20?
- Graphing Complex and Real Numbers [02/26/2003]
Since on the Cartesian plane we can only graph real zeros and real
solutions, are we truly graphing the function when we omit the complex
and imaginary zeros and solutions?
- Graphing Direct Variation [02/27/2003]
How do you graph direct variation? I thought you had to have two
coordinates to graph a line.
- Graphing Equations [08/15/1997]
I know the coordinates of these equations, but what are the names and how
do I graph them?
- Graphing f(2x) and f(|x|) [09/03/2003]
Given f(x), how do you graph f(2x) and f(|x|)?