y-7=-2(x+8)graph the following function... really don't now how to figure this out.

your function is a straight line

- from your equation we can tell that the slope is -2 and the line passes through (-8,7)
All you need is another point and you can draw it.
Why not pick something nice like x = 0
So we get:
y-7 = -2(8)
y = -16+7 = -9

take over