Example 13 from Algebra and Trigonometry, 1.1 Real Numbers: Algebra Essentials

Simplifying a Formula

A rectangle with length $L$ and width $W$ has a perimeter $P$ given by $P = L + W + L + W .$ Simplify this expression.

Work it out on paper first. Then open the solution one step at a time, and stop as soon as you can finish on your own.

Solution
$\begin{matrix} P & = & L + W + L + W \\ P & = & L + L + W + W & Commutative property of addition \\ P & = & 2 L + 2 W & Simplify \\ P & = & 2 (L + W) & Distributive property \end{matrix}$

Your turn

The book's Try It right after this example: same idea, new numbers. Only the answer is given.

If the amount $P$ is deposited into an account paying simple interest $r$ for time $t,$ the total value of the deposit $A$ is given by $A = P + P r t .$ Simplify the expression. (This formula will be explored in more detail later in the course.)

How did it go?

Your turn

The book's Try It right after this example: same idea, new numbers. Only the answer is given.

Solution

Your turn

Solution

Your turn