Algebra 1A 2.1-2.4 Review

2.1 Use Integers and Rational Numbers

100

True or false: All integers are rational numbers, but not all rational numbers are integers.

True

200

Classify the numbers as whole numbers, integers, and rational numbers. State all the possibilities for every number:

3, -4.1, -7, 109,000

3: Whole, integer, and rational

-4.1: rational

-7: integer and rational

109,000: whole, integer, and rational

300

Evaluate the expression 1 + l-xl when x = -9.1

10.1

400

Put these rational numbers in order from least to greatest:

-4, 5, -17.1, -(-6.2001)

-17.1, -4, 5, -(-6.2001)

500

Define a rational number ACCURATELY

A number that can be written as a/b where a and b are integers and b does not equal zero.

2.2 Adding Real Numbers

100

8 + (-11)

-3

200

-5.3 + (-4.9)

-10.2

300

If x = 2.4, evaluate -1.7 + (-5.4) + (-x)

-9.5

400

Which property of addition is illustrated here?

(x + 9) + 2 = x + (9 + 2)

Associative property of addition

500

Page 79, #57a

Your friend has the better score at -2. You have -1.

2.3 Subtracting Real Numbers

100

18 - (-7)

25

200

Evaluate the expression when x=7.1 and y=-2.5

-y - (1.9 - x)

-1.9

300

Find the change in elevation:

36.4 feet above sea level to -90.7 feet below sea level.

-127.1 feet

400

Evaluate when x=3.6, y=-6, and z=-11

(x - y) - lzl

-1.4

500

The temperature inside Mammoth Cave in Kentucky is about
12.2 C year round. If the temperature outside the cave is -2.4 C,
what is the change in temperature from outside to inside the cave?

14.6 C

2.4 Multiply Real Numbers

100

-9(-10)

90

200

Identify the illustrated property:

0.3(3) = 3(0.3)

Commutative property of multiplication

300

9(-2/3)(-1/5)

6/5

400

-6r(-2.8r)

16.8r²

500

In 1940 the surface area of the Dead Sea was about
980 square kilometers. From 1940 to 2001, the average rate of change in
surface area was about -5.7 square kilometers per year. Find the surface
area of the Dead Sea in 2001.

632.3 km²