# Systems of Linear Equations

### Topics

## Introduction to :

The best way to learn how to solve a word problem is to do it. Same goes for freestyle swimming, riding a bike, or writing a book about the ideological origins of the American Revolution. Okay, actually the last one could benefit from some preliminary research. You may not want to just dive in on that one.

We've already done the translation for each of the exercises in this section, so don't start claiming "deja vu" if they seem familiar, but it can't hurt to go through them again and solve them this time.

#### Exercise 1

Solve the following word problem:

A forest inhabited only by borogoves and mome raths contains eighty-two creatures. Borogoves are two-legged animals, while a mome rath has 4 legs. If the forest contains a total of 234 legs, how many borogoves and how many mome raths live in the forest?

#### Exercise 2

Solve the following word problem:

Blue beads cost $0.50 per ounce and green beads cost $0.75 per ounce. Janine wants to mix blue and green beads to get 10 ounces of a bead mixture worth $0.55 per ounce. How many ounces of each color does Janine need to buy?

#### Exercise 3

Solve the following word problem:

Ayako spent $7.80 on equal weights of white and red beads. The red beads cost twice as much per ounce as the white beads. How much did Ayako spend on each color of beads?

#### Exercise 4

Solve the following word problem:

A rectangle has perimeter 18. If each side of the rectangle is doubled, the perimeter of the new rectangle is 36. What were the dimensions of the original rectangle?

#### Exercise 5

Solve the following word problem:

Jemima wants to make chocolate-chip walnut brownies. Chocolate chips come in a 12oz bag that costs $3. Walnuts come in a 4oz bag that costs $2. If Jemima needs three pounds of chocolate chips and walnuts combined, and has $15 to spend, how many bags of each can she buy?