It should be, 106040 I hope this helps.
A. The relationship is not proportional because his savings account started with $100 and then he adds 20 each month.
b. To make it proportional Ralph's savings account needs to start with $0.
40% of 20 is 8
8 is the answer
The cross of the position vectors is
.. [5, 2, 2] × [6, -1, 1] = [4, 7, -17] . . . . . the normal vector of the desired plane
Since the origin is a point in the plane, its equation can be written as
.. 4x +7y -17z = 0
That would be one I guess
