All Advanced Geometry Resources
Example Questions
Example Question #8 : Graphing A Quadratic Function
has as its graph a vertical parabola on the coordinate plane. You are given that and , but you are not given .
Which of the following can you determine without knowing the value of ?
I) Whether the graph is concave upward or concave downward
II) The location of the vertex
III) The location of the -intercept
IV) The locations of the -intercepts, if there are any
V) The equation of the line of symmetry
I and V only
I and III only
III and IV only
I, II, and V only
I, III, and IV only
I and III only
I) The orientation of the parabola is determined solely by the sign of . Since , the parabola can be determined to be concave downward.
II and V) The -coordinate of the vertex is ; since you are not given , you cannot find this. Also, since the line of symmetry has equation , for the same reason, you cannot find this either.
III) The -intercept is the point at which ; by substitution, it can be found to be at . known to be equal to 9, so the -intercept can be determined to be .
IV) The -intercept(s), if any, are the point(s) at which . This is solvable using the quadratic formula
Since all three of and must be known for this to be evaluated, and only is known, the -intercept(s) cannot be identified.
The correct response is I and III only.
Example Question #161 : Coordinate Geometry
Which of the following equations can be graphed with a vertical parabola with exactly one -intercept?
The graph of has exactly one -intercept if and only if
has exactly one solution - or equivalently, if and only if
Since in all three equations, , we find the value of that makes this statement true by substituting and solving:
The correct choice is .
Example Question #61 : Graphing
has as its graph a vertical parabola on the coordinate plane. You are given that , but you are given neither nor .
Which of the following can you determine without knowing the values of and ?
I) Whether the curve opens upward or opens downward
II) The location of the vertex
III) The location of the -intercept
IV) The locations of the -intercepts, if there are any
V) The equation of the line of symmetry
V only
III only
III and IV only
I only
II and V only
I only
I) The orientation of the parabola is determined solely by the value of . Since , the parabola can be determined to open upward.
II and V) The -coordinate of the vertex is ; since you are not given , you cannot find this. Also, since the line of symmetry has equation , for the same reason, you cannot find this either.
III) The -intercept is the point at which ; by substitution, it can be found to be at . is unknown, so the -intercept cannot be found.
IV) The -intercept(s), if any, are the point(s) at which . This is solvable using the quadratic formula
Since all three of and must be known for this to be evaluated, and only is known, the -intercept(s) cannot be identified.
The correct response is I only.
Example Question #31 : Graphing
The parabolas of the functions and on the coordinate plane have the same vertex.
If we define , which of the following is a possible equation for ?
None of the other responses gives a correct answer.
The eqiatopm of is given in the vertex form
,
so the vertex of its parabola is . The graphs of and are parabolas with the same vertex, so they must have the same values for and .
For the function , and .
Of the five choices, the only equation of that has these same values, and that therefore has a parabola with the same vertex, is .
To verify, graph both functions on the same grid.
Example Question #162 : Coordinate Geometry
Give the vertex of the graph of the function
.
This can be answered rewriting this expression in the form
.
Once this is done, we can identify the vertex as the point .
The vertex is
Example Question #163 : Coordinate Geometry
has as its graph a vertical parabola on the coordinate plane. You are given that and , but you are not given the value of .
Which of the following can you determine without knowing the value of ?
I) Whether the graph is concave upward or concave downward
II) The location of the vertex
III) The location of the -intercept
IV) The locations of the -intercepts, if there are any
V) The equation of the line of symmetry
I, III, and IV only
I, II, and V only
II and V only
III and IV only
I and V only
I and V only
I) The orientation of the parabola is determined solely by the sign of . Since , a positive value, the parabola can be determined to be concave upward.
II) The -coordinate of the vertex is ; since you given both and , you can find this to be
The -coordinate is equal to . However, you need the entire equation to determine this value; since you do not know , you cannot find the -coordinate. Therefore, you cannot find the vertex.
III) The -intercept is the point at which ; by substitution, it can be found to be at . is unknown, so the -intercept cannot be found.
IV) The -intercept(s), if any, are the point(s) at which . This is solvable using the quadratic formula
Since all three of and must be known for this to be evaluated, and is unknown, the -intercept(s) cannot be identified.
V) The line of symmetry has equation . When exploring the vertex, we found that this value is equal to , so the line of symmetry is the line of the equation .
The correct response is I and V only.
Example Question #164 : Coordinate Geometry
has as its graph a vertical parabola on the coordinate plane. You are given that , but you are given no other information about these values.
Which of the following can you determine without knowing the value of ?
I) Whether the graph is concave upward or concave downward
II) The location of the vertex
III) The location of the -intercept
IV) The locations of the -intercepts,or whether there are any
V) The equation of the line of symmetry
II, IV, and V only
I, IV, and V only
II and V only
I, II, IV, and V only
IV and V only
I, IV, and V only
I) The orientation of the parabola is determined solely by the sign of . It is given in the problem that is negative, so it follows that the parabola is concave downward.
II) The -coordinate of the vertex is ; since , this number is . The -coordinate is , but since we do not know the values of , , and , we cannot find this value. Therefore, we cannot know the vertex.
III) The -intercept is the point at which ; by substitution, it can be found to be at . is unknown, so the -intercept cannot be found.
IV) The -intercept(s), if any, are the point(s) at which . This is solvable using the quadratic formula
Since , this can be rewritten and simplified as follows:
However, since has no real square root, has no real solutions, and its graph has no -intercepts.
V) The line of symmetry has equation . When exploring the vertex, we found that this value is equal to , so the line of symmetry is the line of the equation .
The correct response is I, IV, and V only.
Example Question #62 : Coordinate Geometry
The graphs of the functions and have the same pair of -intercepts.
If we define , which of the following is a possible definition of ?
The -intercepts of the parabola
can be determined by setting and solving for :
or
The intercepts of the parabola are and .
We can check each equation to see whether these two ordered pairs satisfy them.
:
Each of these equations has a parabola that does not have as an -intercept. However, we look at
and are also -intercepts of the graph of this function, so this is the correct choice.
Example Question #63 : Coordinate Geometry
A vertical parabola has two -intercepts, one at and one at .
Which of the following must be true about this parabola?
None of the statements in the other choices must be true.
The parabola must have as its vertex.
The parabola must be concave downward.
The parabola must have its -intercept at .
The parabola must have the line of the equation as its line of symmetry.
The parabola must have the line of the equation as its line of symmetry.
A parabola with its -intercepts at and at has as its equation
for some nonzero . If this is multiplied out, the equation can be rewritten as
or, simplified,
The sign of quadratic coefficient determines whether it is concave upward or concave downward. We do not have the sign or any way of determining it.
The -coordinate of the -intercept is the contant, , but without knowing , we have no way of knowing .
The -coordinate of the vertex of is the value . since , this expression becomes
The -coordinate is
,
but without knowing , this coordinate, and the vertex itself, cannot be determined.
The line of symmetry is the line ; this value was computed to be equal to 6, so the line can be determined to be .
Example Question #165 : Coordinate Geometry
Which of the following is the equation of the line of symmetry of a vertical parabola on the coordinate plane with its vertex at ?
The line of symmetry of a vertical parabola is a vertical line, the equation of which takes the form for some . The line of symmetry passes through the vertex, which here is , so the equation must be .
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