-3w= -7w-7 =
-3w+7w = -7w+7w - 7 =
4w= -7
4w/4 = -7/4 =
w = -7/4
The minutes will be ur x axis and the cm of snow will be ur y axis
(10,2),(30,3.6).....using 2 points and the slope formula : (y2 - y1) / (x2 - x1)
slope = (3.6 - 2) / (30 - 10) = 1.6 / 20 = 0.08 cm per minute <===