You are given
two points, (-1, 10) and (5, 8). You are required to find the equation in slope
intercept form given the points. The equation of a slope intercept form is y =
mx + b. Where m is the slope and b is the y-intercept. By definition, slope, m,
is the rise over run or the difference of y over the difference of x.
m =
y2-y1/x2-x1
Let us denote
y2=8, y1=10, x2=5 and x1=-1 and we get
m =
8-10/5-(-1)
m = -1/3,
a negative slope means it is rising to the left of the graph.
Since the
slope passes the two points, it also passes the y-intercept. Choose one of the
points, (-1, 10) and substitute it to y = mx + b.
y = mx + b
10 =
(-1/3)(-1) + b
b = 29/3
The
equation now is y = -1/3x + 29/3.
