<em>X = 2 cm</em>
Volume = Bh= 8×5×1/2×X= 80
X = 80/20 = 4
First find the slope, take derivative of both sides with respect to x.
2y dy/dx=3x^2+6x
solve for dy/dx
dy/dx=[3x^2+6x]/2y
plug in given vales of (1,2(
dy/dx=9/4
now you have everything you need to plug into point slope form
y-2=(9/4)(x-1)
answer is y=(9/4)x+(1/4)
Um I think the first one is non proportional and the 2nd one is proportional y is 5 times x the 5 might be a negative