All GRE Math Resources
Example Questions
Example Question #243 : Geometry
What is the equation of a line passing through the two points and ?
Based on the information provided, you can find the slope of this line easily. From that, you can use the point-slope form of the equation of a line to compute the line's full equation. The slope is merely:
Now, for a point and a slope , the point-slope form of a line is:
Let's use for our point
This gives us:
Now, distribute and solve for :
Example Question #243 : Geometry
What is the equation of a line passing through with a -intercept of ?
Based on the information that you have been provided, you can quickly find the slope of your line. Since the y-intercept is , you know that the line contains the point . Therefore, the slope of the line is found:
Based on this information, you can use the standard slope-intercept form to find your equation:
, where and
Example Question #244 : Geometry
Given the graph of the line below, find the equation of the line.
To solve this question, you could use two points such as (1.2,0) and (0,-4) to calculate the slope which is 10/3 and then read the y-intercept off the graph, which is -4.
Example Question #111 : Algebra
Which line passes through the points (0, 6) and (4, 0)?
y = 1/5x + 3
y = 2/3x –6
y = –3/2x + 6
y = –3/2 – 3
y = 2/3 + 5
y = –3/2x + 6
P1 (0, 6) and P2 (4, 0)
First, calculate the slope: m = rise ÷ run = (y2 – y1)/(x2 – x1), so m = –3/2
Second, plug the slope and one point into the slope-intercept formula:
y = mx + b, so 0 = –3/2(4) + b and b = 6
Thus, y = –3/2x + 6
Example Question #278 : Ssat Upper Level Quantitative (Math)
What line goes through the points (1, 3) and (3, 6)?
4x – 5y = 4
3x + 5y = 2
–3x + 2y = 3
2x – 3y = 5
–2x + 2y = 3
–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 #1 : Other 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 #2 : How To Find The Equation Of A Line
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 #731 : Act Math
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 #1 : 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 #1 : How To Find The Equation Of A Line
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.