77.

78.

To solve for r when the

and the x vector are given, use

the function formula:

Isolate unknown:

r = _____________

78.

79.

Solve for the r vector.

Use formula:

Isolate unknowns:

r = _____________

Substitute in values:

r = _____________

Use trig tables:

r = _____________

Solution:

r = _____________

79.

r = 200

80.

Solve for

. Which function formula is used?

If your answer is

other than the one

above, go to the

COS column of

the trig tables and

see if you used

the cosine of 24.5

, which is .9100.

= _________________

80.

81.

To solve for x when the

and the r vector are given, use the

function formula:

NOTE: Angle θ is

the angle between

the x and r vectors.

The unknown isolated: x = ________________