Answer:
The answer is 46.5 minutes
Explanation:
The tangent plane is a point-slope shape that is used in two dimensions.
This is written as y - y0 = m (x-x0), or its similar function notation (and moves y0 = f (x0) to the other side):
f (x) = f (x0) + fx (x0) (x-x0)
In the case where more dimensions are used, this will be equal to:
f (t, x) = f (t0, x0) + ft (t0, x0) (t-t0) + fx (t0, x0) (x-x0)
Replacing, we have:
f (t, x) = 50 + -5/3 (t-t0) + -3/2 (x-x0)
for the point t = 33, x = 4, we have:
f (33.4) ≈ 50 + -5 / 3 * (33-30) + -3/2 * (4-5) = 50-5 + 3/2 = 46.5 minutes