We need to find m and b to find in the equation of a line:
y = mx + b
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slope y-intercept
To find m, the slope, we need to find the rise over the run of the line. You pick two points and use the y values finding the difference of them and do the same for the x values and put them on the bottom. Let's use the points (0, -2) and (4, 0):
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(x₁, y₁) (x₂, y₂)
m = (y₂ - y₁)/(x₂ - x₁)
m = (-2 - 0)/(0 - 4)
m = (-2)/(-4)
m = 1/2
The slope is positive since the line is going upward from left to right.
Now we need b, the y intercept, where the line intersects with the y axis, simply by looking at the graph. b is -2.
Thus, the answer is C. y = 1/2x - 2.
