What is the equation of the line that passes through the points (-8,8) and (4,-1)​

y = (-3/4)x + 2

Step-by-step explanation:

Find the slope of this line.  Note how the first x-coordinate (-8) becomes 4, a jump of 12, and how the first y-coordinate (8) becomes -1, a decrease of 9.  Then the slope is

m = (change in y) / (change in x) = -9/12 = m = -3/4

Find the y-intercept from this data using the slope-intercept form:

y = mx + b becomes  8 = (-3/4)(-8) + b when x = -8, y = 8 and m = -3/4.

Solving this equation for b, we get:

                                     8 = 6 + b, so that b must be 2.

The desired equation is y = (-3/4)x + 2.

if the eqn of the parabola is f(x) = (x-4)(x+2), we need to mult. this out to find the coordinates of the vertex.

then f(x) = x^2 + 2x - 4x - 8, and f(x) = x^2 - 2x - 8.

one way in which you can find the vertex is to calculate x = -b / (2a).   here, that comes to

        )

x = = 1.   f(1) = 1^2 - 2(1) - 8 = - 9.   vertex is at (1, -9).

        2(1) 

find another point on the curve:   let x=0, for which y=-8.   then (0, -8) is on the curve.   plot the vertex and this point and draw a smooth parabola thru both.

hope this