How to find x or y intercept - GRE Quantitative Reasoning
Card 0 of 4
What is the y-intercept of the line that goes through the points (–2, 1) and (5, 6)?
What is the y-intercept of the line that goes through the points (–2, 1) and (5, 6)?
The slope can be calculated from m = (y2 – y1)/(x2 – x1) = (6 – 1)/(5 + 2). Having calculated the slope, we can now use point-slope form of a line, y – y1 = m(x – x1), and using the second point (5, 6): y – 6 = (5/7)(x – 5). This can be rearranged into slope-intercept form to obtain: y = (5/7)x + (17/7). Because the equation is now in slope intercept form, we know that the y-intercept is 17/7.
The slope can be calculated from m = (y2 – y1)/(x2 – x1) = (6 – 1)/(5 + 2). Having calculated the slope, we can now use point-slope form of a line, y – y1 = m(x – x1), and using the second point (5, 6): y – 6 = (5/7)(x – 5). This can be rearranged into slope-intercept form to obtain: y = (5/7)x + (17/7). Because the equation is now in slope intercept form, we know that the y-intercept is 17/7.
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Find the x-intercept of the equation 
Find the x-intercept of the equation
The answer is 10.
In order to find the x-intercept we simply let all the y's equal 0
The answer is 10.
In order to find the x-intercept we simply let all the y's equal 0
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Quantity A:
The 
-intercept of the line 
Quantity B:
The 
-intercept of the line
Quantity A:
The
Quantity B:
The
The key to these quantitative comparison problems is to figure out the worth of both quantities, or figure out whether evaluating the quantities is even possible. In this case, evaluating the quantities is a fairly straightforward case of figuring out the intercepts of two different lines, which is possible. Therefore, you can already discount "the relationship cannot be determined from the information given".
To solve quantity A: 
is in 
form, where 
is the 
-intercept. Therefore, the 
-intercept is equal to 
.
To solve quantity B: 
, you have to sole for the 
intercept. The quickest way to figure out the answer is to remember that the 
axis exists at the line 
, therefore to find out where the line crosses the 
axis, you can set 
and solve for 
.
-3.5 = .5x - 1.5
Both quantity A and quantity B 
, therefore the two quantities are equal.
The key to these quantitative comparison problems is to figure out the worth of both quantities, or figure out whether evaluating the quantities is even possible. In this case, evaluating the quantities is a fairly straightforward case of figuring out the intercepts of two different lines, which is possible. Therefore, you can already discount "the relationship cannot be determined from the information given".
To solve quantity A:
To solve quantity B:
Both quantity A and quantity B
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What is the 
-intercept of the following equation?
What is the
To find the 
-intercept, you must plug 
in for 
.
This leaves you with
.
Then you must get you by itself so you add 
to both sides
.
Then divide both sides by 
to get
.
For the coordinate point, 
goes first then 
and the answer is 
.
To find the
This leaves you with
Then you must get you by itself so you add
Then divide both sides by
For the coordinate point,
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