7. Solve 4x - 8y = 72 for y. * please help m

 y-intercept = 18/-2 = simplified: 9/-1 = decimal form: -9.00000

Step-by-step explanation: Rearrange the equation by subtracting what is to the right of the equal sign from both sides of the equation :

                    4*x-8*y-(72)=0

Solve   x-2y-18  = 0

"y=mx+b" is the formula of a straight line drawn on Cartesian coordinate system in which "y" is the vertical axis and "x" the horizontal axis.

In this formula :

y tells us how far up the line goes

x tells us how far along

m is the Slope or Gradient i.e. how steep the line is

b is the Y-intercept i.e. where the line crosses the Y axis

The X and Y intercepts and the Slope are called the line properties. We shall now graph the line  x-2y-18  = 0 and calculate its properties

Notice that when x = 0 the value of y is 9/-1 so this line "cuts" the y axis at y=-9.00000

 y-intercept = 18/-2 = 9/-1  = -9.00000