Algebra I - Math
Card 1 of 388
Which one of these equations accurately describes a circle with a center of
and a radius of
?
Which one of these equations accurately describes a circle with a center of and a radius of
?
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The standard formula for a circle is
, with
the center of the circle and
the radius.
Plug in our given information.


This describes what we are looking for. This equation is not one of the answer choices, however, so subtract
from both sides.

The standard formula for a circle is , with
the center of the circle and
the radius.
Plug in our given information.
This describes what we are looking for. This equation is not one of the answer choices, however, so subtract from both sides.
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What line goes through points
and
?
What line goes through points and
?
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First, we find the slope between the two points:
and 

Plug the slope and one point into the slope-intercept form to calculate the intercept:



Thus the equation between the points becomes
.
First, we find the slope between the two points:
and
Plug the slope and one point into the slope-intercept form to calculate the intercept:
Thus the equation between the points becomes .
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Find the equation of a line perpendicular to 
Find the equation of a line perpendicular to
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Since a perpendicular line has a slope that is the negative reciprocal of the original line, the new slope is
. There is only one answer with the correct slope.
Since a perpendicular line has a slope that is the negative reciprocal of the original line, the new slope is . There is only one answer with the correct slope.
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Which of the following lines will be parallel to
?
Which of the following lines will be parallel to ?
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Two lines are parallel if they have the same slope. When a line is in standard
form, the
is the slope.
For the given line
, the slope will be
. Only one other line has a slope of
: 
Two lines are parallel if they have the same slope. When a line is in standard form, the
is the slope.
For the given line , the slope will be
. Only one other line has a slope of
:
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Are the following lines parallel?


Are the following lines parallel?
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By definition, two lines are parallel if they have the same slope. Notice that since we are given the lines in the
format, and our slope is given by
, it is clear that the slopes are not the same in this case, and thus the lines are not parallel.
By definition, two lines are parallel if they have the same slope. Notice that since we are given the lines in the format, and our slope is given by
, it is clear that the slopes are not the same in this case, and thus the lines are not parallel.
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Which of the following equations are parallel to
?
Which of the following equations are parallel to ?
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For one equation to be parallel to another, the only requirement is that they must have the same slope. In order to figure out which answer choice is parallel to the given equation, you must first find the slope of the equation:



From the simplified equation, you can see that the slope is
.
The answer choice that has the same slope is
.
For one equation to be parallel to another, the only requirement is that they must have the same slope. In order to figure out which answer choice is parallel to the given equation, you must first find the slope of the equation:
From the simplified equation, you can see that the slope is .
The answer choice that has the same slope is .
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What is the length of a line with endpoints at
and
?
What is the length of a line with endpoints at and
?
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The formula for the length of a line is very similiar to the pythagorean theorem:

Plug in our given numbers to solve:







The formula for the length of a line is very similiar to the pythagorean theorem:
Plug in our given numbers to solve:
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The points A, B, and C reside on a line segment. B is the midpoint of AC. If line AB measures 6 units in length, what is the length of line AC?
The points A, B, and C reside on a line segment. B is the midpoint of AC. If line AB measures 6 units in length, what is the length of line AC?
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If B is the midpoint of AC, then AC is twice as long as AB. We are told that AB=6.

The diagram shows six units between points A and B, with B as the midpoint of segment AC. Therefore segment BC is also six units long, so line AC is twelve units long.

If B is the midpoint of AC, then AC is twice as long as AB. We are told that AB=6.
The diagram shows six units between points A and B, with B as the midpoint of segment AC. Therefore segment BC is also six units long, so line AC is twelve units long.
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What is the length of a line with endpoints
and
?
What is the length of a line with endpoints and
?
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The formula for the length of a line is very similiar to the pythagorean theorem:

Plug in our given numbers to solve:







The formula for the length of a line is very similiar to the pythagorean theorem:
Plug in our given numbers to solve:
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What is the length of a line segment with end points
and
?
What is the length of a line segment with end points and
?
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The formula for the length of line is the distance formula, which is very similar to the Pythagorean theorem.

Plug in the given values and solve for the length.






The formula for the length of line is the distance formula, which is very similar to the Pythagorean theorem.
Plug in the given values and solve for the length.
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If a line has a midpoint at
, and the endpoints are
and
, what is the value of
?
If a line has a midpoint at , and the endpoints are
and
, what is the value of
?
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The midpoint of a line segment is halfway between the two
values and halfway between the two
values.
Mathematically, that would be the average of the coordinates:
.
Plug in the
values from the given points.

Now we can solve for the missing value.


The
values reduce, so both
values equal
. Now we need to create a new equation to solve for the
value.

Multiply both sides by
to solve.


The midpoint of a line segment is halfway between the two values and halfway between the two
values.
Mathematically, that would be the average of the coordinates: .
Plug in the values from the given points.
Now we can solve for the missing value.
The values reduce, so both
values equal
. Now we need to create a new equation to solve for the
value.
Multiply both sides by to solve.
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What would be the length of a line with endpoints at
and
?
What would be the length of a line with endpoints at and
?
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The formula for the length of line is the distance formula, which is very similar to the Pythagorean theorem.

Plug in the given values and solve for the length.






The formula for the length of line is the distance formula, which is very similar to the Pythagorean theorem.
Plug in the given values and solve for the length.
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If a line has a length of
, and the endpoints are
and
, what is the value of
?
If a line has a length of , and the endpoints are
and
, what is the value of
?
Tap to reveal answer
The formula for the length of a line, l, is the distance formula, which is very similar to the Pythagorean Theorem.

Note that the problem has already given us a value for the length of the line. That means
. Plug in all of the given values and solve for the missing term.



Subtract
from both sides.




The formula for the length of a line, l, is the distance formula, which is very similar to the Pythagorean Theorem.
Note that the problem has already given us a value for the length of the line. That means . Plug in all of the given values and solve for the missing term.
Subtract from both sides.
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What line goes through the points
and
?
What line goes through the points and
?
Tap to reveal answer
Find the slope between the two points:

Next, use the slope-intercept form of the equation:
or
where 
So the equation becomes
or in standard form
.
Find the slope between the two points:
Next, use the slope-intercept form of the equation:
or
where
So the equation becomes or in standard form
.
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What is the length of a line with endpoints at
and
?
What is the length of a line with endpoints at and
?
Tap to reveal answer
The formula for the length of a line is very similiar to the pythagorean theorem:

Plug in our given numbers to solve:







The formula for the length of a line is very similiar to the pythagorean theorem:
Plug in our given numbers to solve:
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What is the equation, in slope-intercept form, of the perpendicular bisector of the line segment that connects the points
and
?
What is the equation, in slope-intercept form, of the perpendicular bisector of the line segment that connects the points and
?
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First, calculate the slope of the line segment between the given points.

We want a line that is perpendicular to this segment and passes through its midpoint. The slope of a perpendicular line is the negative inverse. The slope of the perpendicular bisector will be
.
Next, we need to find the midpoint of the segment, using the midpoint formula.

Using the midpoint and the slope, we can solve for the value of the y-intercept.




Using this value, we can write the equation for the perpendicular bisector in slope-intercept form.

First, calculate the slope of the line segment between the given points.
We want a line that is perpendicular to this segment and passes through its midpoint. The slope of a perpendicular line is the negative inverse. The slope of the perpendicular bisector will be .
Next, we need to find the midpoint of the segment, using the midpoint formula.
Using the midpoint and the slope, we can solve for the value of the y-intercept.
Using this value, we can write the equation for the perpendicular bisector in slope-intercept form.
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What is the distance between points
and
?
What is the distance between points and
?
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Use the distance formula:

Plug in the given points:


Use the distance formula:
Plug in the given points:
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Find the distance between points
and
.
Find the distance between points and
.
Tap to reveal answer
Use the distance formula:

Substitute the given points into the formula:


Use the distance formula:
Substitute the given points into the formula:
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What is the length of a line with endpoints of
and
?
What is the length of a line with endpoints of and
?
Tap to reveal answer
The distance formula is just a reworking of the Pythagorean theorem: 
Expand that.

Plug in our given values.





The distance formula is just a reworking of the Pythagorean theorem:
Expand that.
Plug in our given values.
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What is the distance between
and
?
What is the distance between and
?
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Let
and
.
The distance formula is given by
.
Substitute in the given points:

Let and
.
The distance formula is given by .
Substitute in the given points:
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