Algebra 1 : Functions and Lines

Study concepts, example questions & explanations for Algebra 1

varsity tutors app store varsity tutors android store

Example Questions

Example Question #3926 : Algebra 1

Find the length of the line between the points

 and 

Possible Answers:

Correct answer:

Explanation:

To find the length between two points, we use the following distance formula:

where  and  are the points given.

 

Using the given points

 and 

we can substitute into the formula.  We get

 

 

Therefore, the distance between the points  and  is .

Example Question #3926 : Algebra 1

If the line  is connected by the points  and , what is the exact length of this line?

Possible Answers:

Correct answer:

Explanation:

Use the distance formula to determine the distance of this line.

Substitute the points into the equation.

Simplify the radical.

Pull out the common factors.  This radical can still be reduced.

The exact length of the line is:  

Example Question #51 : Points And Distance Formula

Steven and Joel are on a massive grid. Steven is located at point  on the grid and Joel is located at . How far away from each other are they?

Possible Answers:

None of these

Correct answer:

Explanation:

The distance formula is:

Plug in these points into the distance formula.

Reduce:

Example Question #61 : How To Find The Length Of A Line With Distance Formula

Steven and Joel are on a massive grid. Steven is located at point  on the grid and Joel is located at . How far away from each other are they?

Possible Answers:

Cannot be determined

Correct answer:

Explanation:

The distance formula is:

Plug in Seven and Joel's coordinates into this formula.

Example Question #3921 : Algebra 1

What is the distance of the line connected by the points  and ?

Possible Answers:

Correct answer:

Explanation:

Write the distance formula.

Substitute the given points into the formula.

Simplify the terms inside the parentheses.

The answer is: 

Example Question #1 : How To Find Out If A Point Is On A Line With An Equation

Which of the following points is not on the line y = 7x + 2? 

Possible Answers:

(–2, –12)

(0, 2)

(–1, –5)

(2, 16)

(1, 10)

Correct answer:

(1, 10)

Explanation:

To find out if a point (x, y) is on the graph of a line, we plug in the values and see if we get a true statement, such as 10 = 10. If we get something different, like 6 = 4, we know that the point is not on the line because it does not satisfy the equation. In the given choices, when we plug in (1, 10) we get 10 = 7 + 2, which is false, making this is the desired answer.

y = 7x + 2

(2, 16) gives 16 = 7(2) + 2 = 14 + 2 = 16

(–1, –5) gives –5 = 7(–1) + 2 = –7 + 2 = –5

(0, 2) gives 2 = 7(0) + 2 = 0 + 2 = 2

(–2, –12) gives –12 = 7(–2) + 2 = –14 + 2 = –12

All of these are true.

(1, 10) gives 10 = 7(1) + 2 = 7 + 2 = 9

10 = 9 is a false statement.

Example Question #1 : How To Find Out If A Point Is On A Line With An Equation

Which point is on the line ?

Possible Answers:

Correct answer:

Explanation:

To determine whether a point is on a line, simply plug the points back into the equation. When we plug in (2,7) into the equation of  as  and  respectively, the equation works out, which indicates that the point is located on the line.

Example Question #1 : How To Find Out If A Point Is On A Line With An Equation

Which of the following statements is incorrect?

Possible Answers:

The lines  and  are parallel.

 is perpendicular to .

The points  and  lie on the line .

 and  both fall on the line .

Correct answer:

 and  both fall on the line .

Explanation:

Lines that have the same slope are parallel (unless the two lines are identical) and lines with slopes that are opposite-reciprocals are perpendicular. So, the only statements left to evaluate are the two that contain a set of points.

Consider  and .

So the slope, or , is 2.

Plugging the point  into the half-finished equation  gives us a  value of . So that statement is true and the only one that could be the answer is the statement containing  and .

Let's check it just in case.

  gives us a slope value of 6, so we can already tell the equation for the line will not be . We have found our answer.

Example Question #1 : How To Find Out If A Point Is On A Line With An Equation

Which of these lines go through the point (6,5) on an xy-coordinate plane?

Possible Answers:

None of the other answers

Correct answer:

Explanation:

To find out if a point is on a line, you can plug the points back into an equation. If the values equal one another, then the point must be on a line. In this case, the only equation where (6,5) would correctly fit as an  value is .

Example Question #2 : How To Find Out If A Point Is On A Line With An Equation

Which of the following points are on the line described by the equation?

 

Possible Answers:

Two of these answer choices are correct.

Correct answer:

Two of these answer choices are correct.

Explanation:

The easiest way to find out if a point falls on a specific line is to plug the first value of the point in for  and the second value for .

If we do this for , we find that

 

which is true.

The equation also holds true for , but is false for the other values. So, two of the answer choices are correct.

Learning Tools by Varsity Tutors