First of all, remember that parallel lines are those with equivalent slope. So, the given line is
[tex]y=4x+8[/tex]If the new line we have to find is parallel to this one, that means the slope is
[tex]m=4[/tex]Because the coefficient of x is always the slope.
Now, we know that the new line must pass through (1,8) and it must have a slope of 4. We can use the point-slope formula
[tex]y-y_1=m(x-x_1)[/tex]Replacing the point and the slope, we have
[tex]y-8=4(x-1)[/tex]Then, we solve for y
[tex]y=4x-4+8\rightarrow y=4x+4[/tex]Therefore, the new parallel line is
[tex]y=4x+4[/tex]