Just finished doing the math and the correct answer should be B: 5.3 Hope this helps:)
It would be -50 I hope this answers your question
7. A. -18 cm, because it changes -3 cm/per year, so multiply 6 years by -3 cm to get -18 cm
8. D. $20, because it rose +$2 over 10 days, you multiply 10 days by $2 to get $20 total
Answer:

Step-by-step explanation:
We want to find a formula for <em>s</em> in terms of <em>a, b, </em>and cos(x).
Let the point where <em>s</em> intersects AB be D.
Notice that <em>s</em> bisects ∠C. Then by the Angle Bisector Theorem:

We can find BD using the Law of Cosines:

Likewise:

From the first equation, cross-multiply:

And square both sides:

Substitute:

Distribute:

Simplify:

Divide both sides by <em>s </em>(<em>s</em> ≠ 0):

Isolate <em>s: </em>

Factor:

Therefore:

Factor:

Simplify. Therefore:
