Given a standard form equation for a parabola centered at (
h ,
k ), sketch the graph.
Determine which of the standard forms applies to the given equation:
or
Use the standard form identified in Step 1 to determine the vertex, axis of symmetry, focus, equation of the directrix, and endpoints of the latus rectum.
If the equation is in the form
then:
use the given equation to identify
and
for the vertex,
use the value of
to determine the axis of symmetry,
set
equal to the coefficient of
in the given equation to solve for
If
the parabola opens right. If
the parabola opens left.
use
and
to find the coordinates of the focus,
use
and
to find the equation of the directrix,
use
and
to find the endpoints of the latus rectum,
If the equation is in the form
then:
use the given equation to identify
and
for the vertex,
use the value of
to determine the axis of symmetry,
set
equal to the coefficient of
in the given equation to solve for
If
the parabola opens up. If
the parabola opens down.
use
and
to find the coordinates of the focus,
use
and
to find the equation of the directrix,
use
and
to find the endpoints of the latus rectum,
Plot the vertex, axis of symmetry, focus, directrix, and latus rectum, and draw a smooth curve to form the parabola.
Graphing a parabola with vertex (
h ,
k ) and axis of symmetry parallel to the
x -axis
Graph
Identify and label the
vertex ,
axis of symmetry ,
focus ,
directrix , and endpoints of the
latus rectum .
The standard form that applies to the given equation is
Thus, the axis of symmetry is parallel to the
x -axis. It follows that:
the vertex is
the axis of symmetry is
so
Since
the parabola opens left.
the coordinates of the focus are
the equation of the directrix is
the endpoints of the latus rectum are
or
and
Next we plot the vertex, axis of symmetry, focus, directrix, and latus rectum, and draw a smooth curve to form the parabola. See
[link] .
Graphing a parabola from an equation given in general form
Graph
Identify and label the vertex, axis of symmetry, focus, directrix, and endpoints of the latus rectum.
Start by writing the equation of the
parabola in standard form. The standard form that applies to the given equation is
Thus, the axis of symmetry is parallel to the
y -axis. To express the equation of the parabola in this form, we begin by isolating the terms that contain the variable
in order to complete the square.
It follows that:
the vertex is
the axis of symmetry is
since
and so the parabola opens up
the coordinates of the focus are
the equation of the directrix is
the endpoints of the latus rectum are
or
and
Next we plot the vertex, axis of symmetry, focus, directrix, and latus rectum, and draw a smooth curve to form the parabola. See
[link] .
Step 1: Find the mean. To find the mean, add up all the scores, then divide them by the number of scores. ...
Step 2: Find each score's deviation from the mean. ...
Step 3: Square each deviation from the mean. ...
Step 4: Find the sum of squares. ...
Step 5: Divide the sum of squares by n – 1 or N.
The sample of 16 students is taken. The average age in the sample was 22 years with astandard deviation of 6 years. Construct a 95% confidence interval for the age of the population.
Bhartdarshan' is an internet-based travel agency wherein customer can see videos of the cities they plant to visit. The number of hits daily is a normally distributed random variable with a mean of 10,000 and a standard deviation of 2,400
a. what is the probability of getting more than 12,000 hits?
b. what is the probability of getting fewer than 9,000 hits?
Bhartdarshan'is an internet-based travel agency wherein customer can see videos of the cities they plan to visit. The number of hits daily is a normally distributed random variable with a mean of 10,000 and a standard deviation of 2,400.
a. What is the probability of getting more than 12,000 hits