Question 1204681
The first equation is 
 If a second line passes through the points (0,4) and has a slope of -1, find the solution to the system.


Equation of line with slope m and passing through(x1,y1) is

 (0,4) ~(x1,y1) and has a slope of m=-1

y-y1= m(x-x1)

y-4= -1(x-0)

y-4=-x
y=-x+4

substitute y 
y=2x-8.  (given)
-x+4=2x-8

3x=12
x=4

Therefore y = -x+4= 0
 the solution to the system of equations is (4,0)

 *[illustration 40.png].