Parallel lines have equal slopes. so the equation y=-4x+5.has slope of -4 because this is in slope intercept form y=mx+b where m is slope.
so we know a parallel line will have slope -4
we have a point on the line so we will use point slope formula to solve.
y-y1=m(x-x1) where (x1,y1) is point on line
so we get
y-4=-4(x-0) to put in slope intercept form we solve for y
y-4=-4x
y=-4x+4 is an equation of a line parallel to y=-4+5 passing through (0,4)
X=2/-3
7-3x=9
-3x=9-7
-3x=2
-3x/3x=2/-3x
x=2/3
15 packages of you meant to say 2 1/2
Well, without even looking at it, I can say it's a downwards facing parabola, which roots at x = -3 and x = 5. That should do it.