Give the slope-intercept form of the equation of the line that is perpendicular to 2x-4y=17 and contains p(-8,2)

The answer would be Y= -2x-7 if im not mistaken because the slope of the equation is 1/2 and to find the perpendicular equation you take the negative reciprocal so that would make the slope -2 and I believe the y intercept would be -7 if it must go through the point (-8,2)

That would be . . . (15/12)*8 = 10 bags of sand