We are given the equation
y=9−4x
comparing this equation with slope-intercept form y=mx+b
we get slope, m =-4
We have this rule that two parallel lines have same slope
So slope of our line would be m=-4
now we are also given a point (0,7) on the line,
We use this point and slope in the slope intercept form to get y-intercept
y=mx+b
7=-4(0)+b
b=7
so our y intercept is 7 and slope is -4, plugging these two in slope intercept form to get the final equation
y=-4x+7
