Y-Intercept of a Straight Line
Y-Intercept of a Straight Line. Where a line crosses the y-axis of a graph. Just find the value of y when x equals 0. Example: In the above diagram the line crosses the y axis at y = 1. Example: Here the line crosses the y axis at y = ?2. Point. The y-intercept is an (x,y) point with x=0, so we show it like this (try dragging the points). Dec 09, · Although the y-intercept is hidden, it does exist. Use the equation of the function to find the y- intercept. y = 12 x 2 + 48 x + 49 The y-intercept has two parts: the x-value and the y-value.
Last Updated: February 3, References. This article was co-authored by Grace What does the daisy flower mean, MA. Grace Imson is a math teacher with over 40 years of teaching experience. She has taught math at the elementary, middle, high school, and college levels. There are 11 references cited in this article, how do you make your picture a cartoon can be found at the bottom of the page.
This article has been viewedtimes. The y-intercept of an equation is a point where the graph of the equation intersects the Y-axis.
To find the y intercept using the equation of the line, plug in 0 for the x variable and solve for y. If the equation is written in the slope-intercept form, plug in the slope and the x and y coordinates for a point on the line to solve for y. If you don't know the slope, calculate it by dividing the rise of the line by the run. If you want to find the y-intercept if you only know 2 points along the line, keep reading the article!
Cookie Settings. Learn why people trust wikiHow. Download Article Explore this Article methods. Tips and Warnings. Related Articles. Article Summary. Method 1 of Write down the slope and point. This type of problem also gives you the x,y coordinate of one point along the graph. Skip to the other methods below if you don't have both these pieces of information.
Example 1: A straight line with slope 2 contains the point -3,4. Find the y-intercept of this line using the steps below. Learn the slope-intercept form of an what is clipboard on galaxy s4. When the equation is in this form, the variable m is the slope, and b is the y-intercept.
Substitute the slope in this equation. Write the slope-intercept equation, but instead of muse the slope of your line. Example 1 cont. Replace x and y with the coordinates of the point. Any time you have the coordinates of a single point on your line, you can substitute those x and y coordinates for the x and y in your line equation. Do this for the equation you've been working on. Solve for b. Remember, b is the y-intercept of the line. Now that b is the only variable in the equation, rearrange to solve for this variable and find the answer.
Write this as a coordinate point. The y-intercept is the point where the line intersects with the y-axis. Method 2 of Write down the coordinates of both points. Example 2: A straight line passes through points -1, 2 and 3, Calculate the rise and run.
Slope is a measure of how much vertical distance the line moves for each unit of horizontal distance. Here's how to find these two quantities from two points: "Rise" is the change in vertical distance, or the difference between the y what does danielle mean in the bible of the two points. Example 2 cont. Divide rise by run to find the slope. Review the slope-intercept form.
Now that we know the slope m and a point x,ywe can use this equation to solve for bthe y-intercept. Fit the slope and point into the equation. Take the equation in slope-intercept form and replace m with the slope you calculated. Replace the x and y terms with the coordinates of a single point on the line. It doesn't matter which point you use. Now the only variable left in the equation is bthe y-intercept. Rearrange the equation so b is on one side, and you have your answer.
Remember, the y-intercept always has an x-coordinate of 0. Method 3 of Write down the equation of the line. If you already have the equation of the line, you can find the y-intercept with a little algebra.
Note: Example 3 is a straight line. See the end of this section for an example of a quadratic equation with a variable raised to the power of 2. Substitute 0 for x. This means any point on the y-axis has an x-coordinate of 0, including the y-intercept of the line. Plug in 0 for x in the line equation. Example 3 cont. Solve for y. The answer is the y-intercept of the line.
The y-intercept of the line is 4. Confirm by graphing optional. To check your answer, graph the equation as neatly as you can. The point where the line crosses the y-axis is the y-intercept. Find the y-intercept for a quadratic equation. A quadratic equation includes a variable x or y raised to the power of 2. You can solve for y with the same substitution, but since the quadratic describes a curve, it could intercept the y-axis at 0, 1, or 2 points.
This means you may end up with 0, 1, or 2 answers. Remember, when taking a square root, you must account for two answers: a negative and a positive. These are both y-intercepts of this curve.
If I have 3, as my points and an x-intercept of one, what would the y-intercept be? Solve by using Method 2 above. You need two points to use that method. One point is given as 3, The second point is the given x-intercept, which is 1,0. Not Helpful 16 Helpful If I am only given one specific point, how can I convert it into slope intercept form?
You can't have only one point. Imagine you're standing in the middle of your neighborhood street and have no where to go. No direction, no distance, etc. You don't need to go to your friend's house or to school. That is an example of having only one point without any other point to go to so there's no line.
Thus, no equation. And more importantly, no math to work out. Not Helpful 20 Helpful Substitute the known slope for m, how to find the y intersept substitute the known point's coordinates for x and y, respectively, in the how to use female condoms pics equation.
Nov 14, · When finding the Y-Intercept from a Graph, all you have to do is find where the line from the equation crosses the y-axis. The point at which the equation crosses the y-axis is the Y-Intercept. When finding the Y-Intercept from a Table, you need to find the y-value from the table when the x-value is equal to zero.
When Finding the Y-Intercept from a Graph and Table you are looking for the point of intersection between the equation and the y-axis. When finding the Y-Intercept from a Graph , all you have to do is find where the line from the equation crosses the y-axis.
The point at which the equation crosses the y-axis is the Y-Intercept. When finding the Y-Intercept from a Table , you need to find the y-value from the table when the x-value is equal to zero.
If the table already has a x-value of zero in it, then all you need to do is look at the y-value. If the table is missing an x-value of zero, then you must use the rate of change to go backwards or forwards to find the x-value of zero. Always be sure to follow the pattern that is shown in the table.
Return To: Home , 8th Grade. When Finding the Y-Intercept from a Graph and Table, you are searching for the point of intersection between the equation and the y-axis.
When finding the Y-Intercept from a Graph, you should find where the line from the equation crosses the y-axis. The point where the equation crosses the y-axis is the Y-Intercept. When finding the Y-Intercept from a Table, you have to discover the y-value from the table when the x-value is equivalent to zero. When the table has a x-value of zero in it, you just check the y-value. When the table does not have a x-value of zero, you should use the slope to go in reverse to discover the x-value of zero.
Watch our free video on how to solve Finding Y Intercept. This video shows how to solve problems that are on our free Finding Y Intercept worksheet that you can get by submitting your email above. This video is about how to find y-intercept. You can get the worksheet used in this video for free by clicking on the link in the description below. The first part of our worksheet is about how to find y-intercept from a graph. In order to find the y-intercept by looking at a graph you have to look at where your line crosses the y axis.
If we wanted to we could go ahead and label our graph. We know that this is the y axis and we know that this is the x axis. The y axis is always a vertical axis and the x axis is always the horizontal axis. If you look at our first example here the line crosses the y axis right here. Number 2 is similar to number 1, we have a graph and we have the equation of a line that crosses the graph.
I went ahead and labeled this is the y axis and this is the x axis. To find the y intercept you have to find where your line crosses the y axis. In the case of this example our line goes through the y axis right here at the origin. The second part is about finding y intercept is about tables. In the case of our first example we can look right at the table we can see that our x value of zero is given to us and we can see that Y is negative When x equals zero that means that the y-intercept for this table will be negative 26 because we already know when x is 0, the Y is negative However sometimes they do not give you an x equals 0.
In order to find the y intercept we have to go backwards to an x equals 0. In the case of this example we have to fill in the 0 in the X column. In order to do that we have to work backwards. If we go this way every time we move up a row we add one to the X. And that will give us X is zero. Now we have to do the same thing for y because we have to find the Y value when X is equal to zero.
When you subtract five you do ten minus five and that gives you five. Now we know when X is equal to zero Y is equal to five so we know now that the y intercept is 5. We have hundreds of math worksheets for you to master. Get Started Now. Join thousands of other educational experts and get the latest education tips and tactics right in your inbox. Leave this field empty if you're human:. How to find Y Intercept Mathcation. Common Core Standard: 8. How to find the Y Intercept of a Table Example.
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