All GRE Math Resources
Example Questions
Example Question #3 : Coordinate Geometry
What line goes through the points (1, 3) and (3, 6)?
–3x + 2y = 3
2x – 3y = 5
4x – 5y = 4
–2x + 2y = 3
3x + 5y = 2
–3x + 2y = 3
If P1(1, 3) and P2(3, 6), then calculate the slope by m = rise/run = (y2 – y1)/(x2 – x1) = 3/2
Use the slope and one point to calculate the intercept using y = mx + b
Then convert the slope-intercept form into standard form.
Example Question #61 : Lines
What is the slope-intercept form of ?
The slope intercept form states that . In order to convert the equation to the slope intercept form, isolate on the left side:
Example Question #1441 : Gre Quantitative Reasoning
A line is defined by the following equation:
What is the slope of that line?
The equation of a line is
y=mx + b where m is the slope
Rearrange the equation to match this:
7x + 28y = 84
28y = -7x + 84
y = -(7/28)x + 84/28
y = -(1/4)x + 3
m = -1/4
Example Question #101 : Algebra
If the coordinates (3, 14) and (–5, 15) are on the same line, what is the equation of the line?
First solve for the slope of the line, m using y=mx+b
m = (y2 – y1) / (x2 – x1)
= (15 – 14) / (–5 –3)
= (1 )/( –8)
=–1/8
y = –(1/8)x + b
Now, choose one of the coordinates and solve for b:
14 = –(1/8)3 + b
14 = –3/8 + b
b = 14 + (3/8)
b = 14.375
y = –(1/8)x + 14.375
Example Question #2 : Coordinate Geometry
What is the equation of a line that passes through coordinates and ?
Our first step will be to determing the slope of the line that connects the given points.
Our slope will be . Using slope-intercept form, our equation will be . Use one of the give points in this equation to solve for the y-intercept. We will use .
Now that we know the y-intercept, we can plug it back into the slope-intercept formula with the slope that we found earlier.
This is our final answer.
Example Question #61 : Geometry
Which of the following equations does NOT represent a line?
The answer is .
A line can only be represented in the form or , for appropriate constants , , and . A graph must have an equation that can be put into one of these forms to be a line.
represents a parabola, not a line. Lines will never contain an term.
Example Question #143 : Coordinate Geometry
Let y = 3x – 6.
At what point does the line above intersect the following:
They do not intersect
(–5,6)
They intersect at all points
(0,–1)
(–3,–3)
They intersect at all points
If we rearrange the second equation it is the same as the first equation. They are the same line.
Example Question #1 : Midpoint Formula
There is a line defined by two end-points, and . The midpoint between these two points is . What is the value of the point ?
Recall that to find the midpoint of two points and , you use the equation:
.
(It is just like finding the average of the two points, really.)
So, for our equation, we know the following:
You merely need to solve each coordinate for its respective value.
Then, for the y-coordinate:
Therefore, our other point is:
Example Question #252 : Geometry
There is a line defined by two end-points, and . The midpoint between these two points is . What is the value of the point ?
Recall that to find the midpoint of two points and , you use the equation:
.
(It is just like finding the average of the two points, really.)
So, for our equation, we know the following:
You merely need to solve each coordinate for its respective value.
Then, for the y-coordinate:
Therefore, our other point is:
Example Question #1 : Midpoint Formula
What is the other endpoint of a line segment with one point that is and a midpoint of ?
Recall that the midpoint formula is like finding the average of the and values for two points. For two points and , it is:
For our points, we are looking for . We know:
We can solve for each of these coordinates separately:
X-Coordinate
Y-Coordinate:
Therefore, our point is