Adding Integers Review

Bell Ringer• A positive + a positive is (always, sometimes,

never) a positive.

• A positive + a positive is (always, sometimes, never) a negative.

• A negative + a negative is (always, sometimes, never) negative.

• A positive + a negative is (always, sometimes, never) a positive.

Bell Ringer• A positive + a positive is (always, sometimes,

never) a positive.o POSITIVE

• A positive + a positive is (always, sometimes, never) a negative.o NEVER

• A negative + a negative is (always, sometimes, never) negative.o ALWAYS

• A positive + a negative is (always, sometimes, never) a positive.o SOMETIMES

Where we were…• Adding integers

o Same signs…o Opposite signs…

• Subtracting Integerso Additive inverse

• Absolute value

Where we are…• Students will learn to…

o Review the rules for adding integers.

Homework

Unit Plan• I can… represent addition and subtraction on a

horizontal number or vertical number line.o Rate yourself and date

• I can… solve real-world and mathematical problems involving the four operations with rational numbers.o Rate yourself and date

Where we are going…• Quiz on Friday

o Adding integers

o Subtracting integers

Adding Integers• Power Write #1

o Describe the rules for adding integers with the same signs…

• Power Write #2

o Describe the rules for adding integers with opposite signs…

Adding Integers• Power Write #1

o Describe the rules for adding integers with the same signs…• Add the numbers, keep the common sign

• Power Write #2

o Describe the rules for adding integers with opposite signs…• Subtract the numbers, keep the sign of the number with the larges

absolute value.

-10 + (-20)• How do you know?

-10 + (-20)• How do you know?• - 30; add and keep the common sign

-20 + (-10)• What property allows you to switch the order of

addition?

-20 + (-10)• What property allows you to switch the order of

addition?• - 30; commutative property

- ½ + (- ½ )

- ½ + (- ½ )• - 1

15 + (-9)

15 + (-9)• 6

-13 + 20

-13 + 20• 7

-7 + ___ = 0• What is this called?

-7 + ___ = 0• What is this called?

• 7; zero pairs, additive inverse, opposites

-9 + 9 + (-14)

-9 + 9 + (-14)• -14

Algebra• The sum of a number and -20 = 40. What is the

number?

Algebra• The sum of a number and -20 = 40. What is the

number?• 60 + (-20) = 40

x + yWhen: x = 5, y = -1

x + yWhen: x = 5, y = -1

5 + (-1) = 4

Word Problem• A football team gained 7 yards on the first play,

lost 9 yards on the second play and gained 6 yards on the third play. To get a first down, they must gain 10 yards on 4 plays.

• Write an addition expression that shows this scenario.

• How many yards will the team need to gain on it’s fourth play to get a first down?

Word Problem• A football team gained 7 yards on the first play,

lost 9 yards on the second play and gained 6 yards on the third play. To get a first down, they must gain 10 yards on 4 plays.

• Write an addition expression that shows this scenario. o 7 + (-9) + 6

• How many yards will the team need to gain on it’s fourth play to get a first down?o They have gained 4 yards, so they need 6 more yards for a first down.

Homework• Adding integers review worksheet

• Due tomorrow.