An investor has $75,000 to invest in a cd and a mutual fund. the cd yields 7% and the mutual fund yields 8%. the mutual fund requires a minimum investment of $8,000, and the investor requires that at least twice as much should be invested in cds as in the mutual fund. how much should be invested in cds and how much in the mutual fund to maximize the return? what is the maximum return? n investor has $80, 000 to invest in a cd and a mutual fund. the cd yields 5% and the mutual fund yields 9%. the mutual fund requires a minimum investment of $10,000, and the investor requires that at least twice as much should be invested in cds as in the mutual fund. how much should be invested in cds and how much in the mutual fund to maximize the return? what is the maximum return?

Draw a diagram to illustrate the problem as shown below.
The origin (0, 0) is the train station.

Part a.
The first train travels 12 miles west and 6 miles north to arrive at A.
It's coordinate is (-12, 6).

The second train travels 20 miles east and 35 miles north to arrive at B.
It's coordinate is (20, 35).

Part b.
The slope of the line from the origin to A is
m = (6 - 0)/(-12 - 0) = -1/2.
The slope is neither vertical nor horizontal.
The y-intercept is 0.

The line OA is given in slope-intercept form by
y = -(1/2)x
In standard form, the line is
y - 6 = -(1/2)*(x - (-12))
or
y - 6 = -(1/2)*(x + 12)

Part c.
The new train station is located at (0, 2) because it is 2 miles north of the old station.
If a new track is built parallel to OA, then it should have a slope of -1/2.
Because it's y-intercept is 2, its equation in slope-intercept form is
y = -(1/2)x + 2.