Find the slope of the line graphed below calculator

Enter the values in the below calculator. Hit the Calculate button to get the slope intercept form of a line using y=mx+b equation.

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Slope intercept form calculator is an online tool that is used to find slope intercept form (equation of line) using two points, y-intercept, or one point and slope.

What is slope intercept form?

Slope intercept is a form of linear equation that can be used to find the equation of a straight line with y intercept and slope of line.

Slope intercept formula

The slope intercept equation can be represented as:

y = mx + b

Where,

x, y represents the x and y coordinates,

m is slope of line, and

b is y intercept.

The equation of slope intercept varies in USA and UK. In UK, variable c is used to represent y-intercept.

 y = mx + c

How to find the slope intercept form (equation of a straight line)?

To find equation of a straight line with slope and y-intercept, follow the example below.

Example:

Find the Straight line equation if y-intercept is 6 and slope is 4.

Solution:

Step 1:Identify the values.

b = 6

m = 4

Step 2:Write the slope form equation and place the values.

y = mx + b

y = 4x + 6

If you need to calculate the slope using two points, use slope calculator.

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How to Calculate Slope From Two Points

The formula for calculating the slope of a straight line from any two points on the line is as follows:

To solve the slope formula, choose any two points on the straight line and designate one of them to be point #1 and the other to be point #2 (regardless of which point you choose for which designation you will still get the same answer).

After designating the two points ...

• The X value from point #1 becomes X1.
• The Y value from point #1 becomes Y1.
• The X value from point #2 becomes X2.
• The Y value from point #2 becomes Y2.

From there you simply substitute the values into the slope formula to solve for m (slope).

Example Problem

Find the slope of a straight line passing through the points (-2,-1) and (4,5).

For this example, we will choose (-2,-1) to be point number one, and (4,5) to be point number two, which means ...

• X1 = -2
• Y1 = -1
• X2 = 4
• Y2 = 5

From there we simply substitute the variables in the slope formula and solve it, like this:

To see how the opposite designation yields the same result, this time we will choose (4,5) to be point number one, and (-2,-1) to be point number two, which means ...

• X1 = 4

• Y1 = 5

• X2 = -2

• Y2 = -1

Solving the formula give us:

So you see, it doesn't matter which point you designate as #1 or #2.

Two Cases to Be Aware Of

If the X coordinates are the same for both points, you will end up with a zero as the denominator. In turn, this means that the slope will be undefined since you can't divide a number by zero. Of course, all this really means is that a line with an undefined slope is a vertical line.

Conversely, if the Y coordinates are the same for both points, the slope will be zero (0 divided by any number is 0). A slope of 0 indicates a horizontal line.

Formulating the Line Equation

Once you have solved for the slope of the line running between the two points, you can then formulate an equation that will find the Y value for any X value, using the following formula:

Using our first example, you would formulate the line equation as follows:

y - y1 = m(x - x1)
y - (-1) = 1(x - (-2))
y = 1x - ((2) + (-1))
y = x + 1

Using the second example, you would formulate the line equation as follows:

In the case of a vertical line, the X value would be the same for any Y value.

In the case of a horizontal line, the Y value would be the same for X value on the line.

How do you find the slope of a line?