What is the y-intercept form?

Y-intercept form refers to the equation y=mx+b, where b is the y-intercept.

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Y-intercept form is often referred to as slope-intercept form. The formula is y=mx+b, where "b" is the y-intercept and "m" is the slope. Using this equation, it is quick to identify the y-intercept since it is the last number in the problem. To graph an equation in this form, one places a point on the y-axis to denote the y-intercept. One can then use the slope to add points on the line. Slope is noted in the equation as "m" and can be seen as a fraction since the slope refers to the number of units up (or down) over the number of units right (or left).

To graph a sample equation such as y=2x+2 which is in y-intercept form, one can place a point at two on the y-axis and then go up two units and right two units for the second point. One can also go down two units and left two units from the original point to find a third point.

A line can also be written with y being equal to a number. In this case, the line is a horizontal line crossing the y-axis. This line has zero slope. One can convert a standard form equation Ax+By=C into y-intercept form by solving for y algebraically.

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