m is the slope
b is the y-intercept.
with a slope of -2, the equation becomes y = -2 * x + b
you are given that the line has an x-intercept of 5.
the x-intercept is the value of x when the value of y is 0.
that would be the coordinate point of (5,0).
what this says is that one of the points on the line is at (5,0).
with a slope of -2, this says that the value of y goes down 2 units when the value of x goes to the right 1 unit.
that's because the slope is the change in the value of y divided by the corresponding change in the value of x.
the slope of -2 assumes you are going from left to right on the graph.
to get to the origin (the point 0,0), the x-value of the coordinate point of (5,0) must go to the left 5 units.
if the change in x is -5 units, then the change in y is -2 times that = 10.
you are going from (5,0) to (0,10).
the coordinate point of (0,10) is the y-intercept.
the y-intercept is the value of y when the value of x is 0.
the slope intercept form of the equation for the straight line becomes y = -2 * x + 10.
the slope is -2.
the y-intercept is 10.
here's what it looks like on a graph.
