Question

Write an equation for the line parallel to the given line that contains
C(4,8);y=-3x+4

Answer 1

parallel line means they have the same slope 
y = mx + b 
where m = slope 
y = -3 + 4
here the slope is negative 3
y = -3x + b
plug in (4, 8)
8 = -3(4) + b 
b = 8 + 12
b = 20

The answer is y = -3x + 20