The slope intercept form is:
y = mx + b
"m" being the slope, "b" being the y-intercept (the y value when x = 0)
For lines to be parallel, the slope has to be the same.
The slope of the given equation is 4, so your parallel line's slope is also 4.
y = 4x + b
The y-intercept is at (0,3), so your y-intercept (y value when x = 0) is 3
y = 4x + 3
