‼️‼️ the questions are on the photo

Slope = (y2 - y1) / (x2 - x1)
slope = (5 + 7)/(10 - 4) = 12/6 = 2

point slope form: 
y - y1 = m(x - 1)
in this case:

If you use point (4,-7) then equation will be:
y -(- 7) = 2(x - 4)
y + 7 = 2(x - 4)

If you use point (10,5) then equation will be:
y - 5 = 2(x - 10)

B. y - 5 = 2(x - 10)

She will need 5/8 bags for each square yard.