The slope-intercept form of a line should be an equation that looks
.
In this equation,
is the slope of the line, and
is the y-coordinate of the y-intercept. That's the point where the line crosses the -axis.
The y-intercept can be found directly from the graph. The line here crosses the -axis at the point . The y-coordinate of that point is (the second number in the tuple.) As a result, .
Finding the slope of this line can take a bit of an effort. Given two points on the line and , the slope of the line would be .
The y-intercept is indeed a point on the graph of the function. That could well be . (In other words, and .)
To get the correct value for , make sure that and are as accurate as possible. Try to take only points that are at the intersection of major gridlines. For example, the point is on the intersection of gridline and . That ensures that the coordinates are quite precise. Since is also on the graph of the function, it could serve as . That means that and .
Calculate :
.
Hence, the equation for this function (in slope-intercept form) would be: