Rewrite the Expression Using Only Positive Exponents, and Simplify $\frac { s ^ { - 1 } + r ^ { - 1 } } { s ^ { - 1 } - r ^ { - 1 } }$

question 63

Multiple Choice

Rewrite the expression using only positive exponents, and simplify. Assume that any variables in the expression are nonzero. $\frac { s ^ { - 1 } + r ^ { - 1 } } { s ^ { - 1 } - r ^ { - 1 } }$

• A) \(\frac { r - s } { r + s }\)
• B) \(s ^ { 2 } + r ^ { 2 }\)
• C) \(\frac { r + s } { r - s }\)
• D) \(\frac { s + r } { s - r }\)
• E) \(\frac { s - r } { s + r }\)

---

Definitions:

Gross Profit

The difference between revenue and the cost of goods sold before accounting for certain other costs.

Periodic Method

An inventory accounting method where the inventory balance is updated at the end of each period after a physical count.

Purchases Discounts

Reductions in price given by suppliers for prompt payment or purchases in bulk.

Merchandise Inventory

A detailed list of all the goods a business holds for the purpose of resale, capturing their quantity and possibly value.