All Algebra 1 Resources
Example Questions
Example Question #11 : How To Find The Equation Of A Line
Which of these lines has a slope of and a -intercept of ?
None of the other answers
When a line is in the form, the is its slope and the is its -intercept. Thus, the only line with a slope of and a -intercept of is
.
Example Question #12 : Slope And Line Equations
What is the equation of a line with a slope of 3 that runs through the point (4,9)?
None of the other answers
You can find the equation by plugging in all of the information to the formula.
The slope (or ) is 3. So, the equation is now .
You are also given a point on the line: (4,9), which you can plug into the equation:
Solve for to get .
Now that you have the and , you can determine that the equation of the line is .
Example Question #13 : Slope And Line Equations
What is the equation of the line passing through the points (1,2) and (3,1) ?
First find the slope of the 2 points:
Then use the slope and one of the points to find the y-intercept:
So the final equation is
Example Question #14 : Slope And Line Equations
What is the slope and y-intercept of ?
Slope: ; y-intercept:
Slope: ; y-intercept:
Slope: ; y-intercept:
None of the other answers
Slope: ; y-intercept:
Slope: ; y-intercept:
The easiest way to determine the slope and y-intercept of a line is by rearranging its equation to the form. In this form, the slope is the and the y-intercept is the .
Rearranging
gives you
which has an of 2 and a of 6.
Example Question #101 : Equations Of Lines
Find the equation of the line, in form, that contains the points , , and .
When finding the equation of a line given two or more points, the first step is to find the slope of that line. We can use the slope equation, . Any combination of the three points can be used, but let's consider the first two points, and .
So is our slope.
Now, we have the half-finished equation
and we can complete it by plugging in the and values of any point. Let's use .
Solving
for gives us
so
We now have our completed equation:
Example Question #16 : Slope And Line Equations
We have two points: and .
If these two points are connected by a straight line, find the equation describing this straight line.
None of these
We need to find the equation of the line in slope-intercept form.
In this formula, is equal to the slope and is equal to the y-intercept.
To find this equation, first, we need to find the slope by using the formula for the slope between two point.
In the formula, the points are and . In our case, the points are and . Using our values allows us to solve for the slope.
We can replace the variable with our new slope.
Next, we need to find the y-intercept. To find this intercept, we can pick one of our given points and use it in the formula.
Solve for .
Now, the final equation connecting the two points can be written using the new value for the y-intercept.
Example Question #17 : Slope And Line Equations
Which of these lines has a slope of and a y-intercept of ?
None of the other answers
Since all of the answers are in the form, the slope of each line is indicated by its and its y-intercept is indicated by its . Thus, a line with a slope of and a y-intercept of must have an equation of .
Example Question #18 : Slope And Line Equations
Find the domain of:
The expression under the radical must be . Hence
Solving for , we get
Example Question #111 : Equations Of Lines
Give, in slope-intercept form, the equation of a line through the points and .
First, use the slope formula to find the slope, setting .
We can write the equation in slope-intercept form as
.
Replace :
We can find by substituting for using either point - we will choose :
The equation is .
Example Question #112 : Equations Of Lines
Give, in slope-intercept form, the equation of a line through the points and .
First, use the slope formula to find the slope, setting .
We can write the equation in slope-intercept form as
.
Replace :
We can find by substituting for using either point - we will choose :
The equation is .