∑ Old Books, New Math

Chapter 6 · Identities and Equations of Condition

Chapter challenge

Ten problems drawn from every lesson in the chapter. Get each one right on your first try for a perfect score. A new set is drawn each time.

0first-try
0of 10 done

From Solving Problems, exercise 12

Solve and check. Use the five steps.

1

The sum of two numbers is 67, and their difference is 5. Find the numbers.

From Representing Numbers, exercise 19

Represent each number.

2

One part of x + y is z. What is the other part?

From Identities and Transposition, exercise 16

Solve by transposing, then check.

3

Solve 3 - 5h + 2 = 7h + 5. What is h?

From Identities and Transposition, exercise 18

Solve by transposing, then check.

4

Solve 14x - 6x = 22 + 17x - 11x. What is x?

From Representing Numbers, exercise 15

Represent each number.

5

One part of x is 4. What is the other part?

From Solving Problems, exercise 6

Solve and check. Use the five steps.

6

What number, tripled and then diminished by 36, gives twice the original number?

From Representing Numbers, exercise 1

Represent each number.

7

Represent a number: Greater than n by 5.

From Representing Numbers, exercise 39

Represent each number.

8

A's age is x years, B's is 2x + 7, and C's is 3x - 8. Express (a) each age five years from now and (b) each age three years ago. Then write equations for: (c) In four years, A's and B's ages will add to 40. (d) Six years ago, C was 24 years older than A. (e) In 10 years A will be as old as B is now. (f) Four years ago C was as old as B will be in 10 years. (g) In x years B will be 40. (h) In 2 years their three ages will add to 100.

From Identities and Transposition, exercise 3

Solve by transposing, then check.

9

Solve 6y - 5 = 9y + 2. What is y?

From Representing Numbers, exercise 22

Represent each number.

10

The difference of two numbers is 18. If the greater is 34, what is the other?