All SAT Math Resources
Example Questions
Example Question #12 : Slope And Line Equations
Equation of line: , = slope, = -intercept
Step 1) Find slope (): rise/run
Step 2) Find -intercept ():
Example Question #21 : Psat Mathematics
Whast line goes through the points and ?
Let and
The slope is geven by: so
Then we use the slope-intercept form of an equation; so
And we convert
to standard form.
Example Question #131 : Lines
What is the equation of the line that passes through the points (4,7) and (8,10)?
In order to find the equation of the line, we will first need to find the slope between the two points through which it passes. The slope, , of a line that passes through the points and is given by the formula below:
We are given our two points, (4,7) and (8,10), allowing us to calculate the slope.
Next, we can use point slope form to find the equation of a line with this slope that passes through one of the given points. We will use (4,7).
Multiply both sides by four to eliminate the fraction, and simplify by distribution.
Subtract from both sides and add twelve to both sides.
This gives our final answer:
Example Question #132 : Lines
Which line contains the following ordered pairs:
and
First, solve for slope.
Then, substitute one of the points into the equation y=mx+b.
This leaves us with the equation
Example Question #1 : How To Find The Equation Of A Line
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 #141 : Coordinate Geometry
Which line passes through the points (0, 6) and (4, 0)?
y = 1/5x + 3
y = 2/3 + 5
y = –3/2 – 3
y = 2/3x –6
y = –3/2x + 6
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 #1 : How To Find The Equation Of A Line
What line goes through the points (1, 3) and (3, 6)?
2x – 3y = 5
4x – 5y = 4
3x + 5y = 2
–3x + 2y = 3
–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 #2 : How To Find The Equation Of A Line
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 #531 : Geometry
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 #1 : Coordinate Geometry
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