Algebra 1 : Equations of Lines

Study concepts, example questions & explanations for Algebra 1

varsity tutors app store varsity tutors android store

Example Questions

Example Question #27 : How To Find The Equation Of A Line

Which is the correct equation for this line?

Graph eq 1

Possible Answers:

Correct answer:

Explanation:

The equation for a line takes the form where m is the slope and b is the y-intercept, where the graph hits the y-axis.

The y-intercept of this line is 1, so b=1.

We can figure out the slope by comparing how far the line goes up vs. how far it goes over between any 2 points. The two most obvious points on the graph are at and . Between these two points, the graph moves down 1 and over 5. This means the slope is , so we'll put that in for m.

The equation is then .

Example Question #28 : How To Find The Equation Of A Line

Which is the correct equation for this line?

Graph eq 2

Possible Answers:

Correct answer:

Explanation:

The equation for a line takes the form where m is the slope and b is the y-intercept, where the graph hits the y-axis.

The y-intercept of this line is -4, so b=-4.

We can figure out the slope by comparing how far the line goes up vs. how far it goes over between any 2 points. The two most obvious points on the graph are at  and . Between these two points, the graph moves up 3 and over 5. This means the slope is , so we'll put that in for m.

The equation is then .

Example Question #31 : How To Find The Equation Of A Line

Find the equation of the line in the form

 

with  through the point .

Possible Answers:

Correct answer:

Explanation:

We are given the slope and a point, which we will plug into .

.

Thus, using the given  and the  you just found, the equation of our line is:

Example Question #31 : Slope And Line Equations

   

Using the data provided, find the equation of the line. 

Possible Answers:

Correct answer:

Explanation:

The equation for a line is always , where  and .

Given two data points, we are able to find the slope, m, using the formula 

.

Using the data points provided, our formula will be: 

, which gives us  or , .

Our y-intercept is given.

Thus our equation for the line containing these points and that y-intercept is .

Example Question #31 : How To Find The Equation Of A Line

Find the equation of a line given the points 

Possible Answers:

Correct answer:

Explanation:

The equation of a line is , where "m" is the slope of the line and "b" is the point at which the line intercepts the y-axis. 

The first thing we must do is use the formula 

 

to find the slope, or "m."

If we plug in the points of the two coordinates given, 

,

we find our slope, "m."

Since our y-intercept is given, we now have everything we need for our equation, 

.

Example Question #34 : How To Find The Equation Of A Line

Find the equation for the line given these two points: 

Possible Answers:

Correct answer:

Explanation:

The equation of a line is , where "m" is the slope of the line and "b" is the point at which the line intercepts the y-axis. 

The first thing we must do is use the formula 

 

to find the slope, or "m."

If we plug in the points of the two coordinates given, 

, we find our slope, "m."

Since our y-intercept is given, we now have everything we need for our equation, 

Example Question #33 : How To Find The Equation Of A Line

Find the equation of the line containing the points:

Possible Answers:

Correct answer:

Explanation:

The equation of a line is , where "m" is the slope of the line and "b" is the point at which the line intercepts the y-axis. 

The first thing we must do is use the formula 

 to find the slope, or "m."

If we plug in the points of the two coordinates given, 

,

we find our slope, "m."

Since our y-intercept is given, we now have everything we need for our equation, 

.

Example Question #34 : How To Find The Equation Of A Line

Find the equation of the lines given the points: 

Possible Answers:

Correct answer:

Explanation:

The equation of a line is , where "m" is the slope of the line and "b" is the point at which the line intercepts the y-axis. 

The first thing we must do is use the formula 

 

to find the slope, or "m."

If we plug in the points of the two coordinates given, 

,

we find our slope, "m."

Since our y-intercept is given, we now have everything we need for our equation, 

.

Example Question #35 : How To Find The Equation Of A Line

Using the data above, find the equation of the line. 

Possible Answers:

Correct answer:

Explanation:

The data provided is enough data to for us to find the equation of a line that passes through these points: 

.

An equation representing a line: 

,

where m = slope, b = y-intercept.

To find the slope use the following formula, 

,

so in this problem the slope: 

.

The y-intercept is given. So our equation is 

Example Question #36 : How To Find The Equation Of A Line

Given this information, find the equation of the line. "This line passes through two points, one of which is  and the other is . The line also passes through the origin.

Possible Answers:

Correct answer:

Explanation:

The data provided is enough data to for us to find the equation of a line that passes through these points: 

.

An equation representing a line: 

,

where m = slope, b = y-intercept.

To find the slope use the following formula, 

,

so in this problem the slope: 

.

The y-intercept is given. So our equation is 

Learning Tools by Varsity Tutors