The slope and y-intercept of a line.
The equation of a line can be expressed as:
y = mx + b
Where m is the slope and b is the y-intercept. The slope of a line that passes through the points (x1,y1) and (x2,y2) is calculated as:
[tex]m=\frac{y_2-y_1}{x_2-x_1}[/tex]The figure shows a horizontal red line. We only need two points (or ordered pairs) to calculate the slope. Let's get them from the graph: (0,-5) and (2,-5).
Calculate the slope:
[tex]m=\frac{-5-(-5)}{2-0}=\frac{-5+5}{2}=0[/tex]The slope is 0.
The y-intercept, as shown in the equation of the line, is the value of y when x=0.
Looking at the graph, we can identify the value of y=-5 when x=0. In fact, y=-5 for any value of x.
Thus, the y-intercept as an ordered pair is (0,-5)