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Using Counters

Objective: Use counters to solve the

addition of negative and positiveintegers.

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Adding positive integers

We already know that the addition of positive

integers results in a like sign answer.

5

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Adding positive integers

We already know that the addition of positive

integers results in a like sign answer.

5 +

+

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Adding positive integers

We already know that the addition of positive

integers results in a like sign answer.

5 + 4

+

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Adding positive integers

We already know that the addition of positive

integers results in a like sign answer.

5 + 4 = 9

+ = 9

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Adding positive integers

We already know that the addition of positive

integers results in a like sign answer. This can be

applied to the addition of negative integers.

5 + 4 = 9

+ = 9

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Adding positive integers

We already know that the addition of positive

integers results in a like sign answer. This can be

applied to the addition of negative integers.

-5

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Adding positive integers

We already know that the addition of positive

integers results in a like sign answer. This can be

applied to the addition of negative integers.

-5 +

+

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Adding positive integers

We already know that the addition of positive

integers results in a like sign answer. This can be

applied to the addition of negative integers.

-5 + (-4)

+

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Adding positive integers

We already know that the addition of positive

integers results in a like sign answer. This can be

applied to the addition of negative integers.

-5 + (-4) =

+ =

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Adding integers with different signs

Rule:Subtract the absolute values of

the integers. The difference will have

the same sign of the integer with thegreatest absolute value.

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Example

Find4 + 5

The absolute value of negative four is four.

The absolute value of positive five is five. The

difference of their absolute values is one. The

largest absolute value is five so the answer

one get the sign of the five which is positive.

So, -4 + 5 = +1

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Alternative MethodUse counters to add unlike signed integers.

-4

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Alternative MethodUse counters to add unlike signed integers.

-4 + 5

+

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Alternative MethodUse counters to add unlike signed integers.

-4 + 5

+

A positive and a negative together become neutral. When

we put a negative with a positive, they go away.

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Alternative MethodUse counters to add unlike signed integers.

-4 + 5

+

A positive and a negative together become neutral. When

we put a negative with a positive, they go away.

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Alternative MethodUse counters to add unlike signed integers.

-4 + 5

+

A positive and a negative together become neutral. When

we put a negative with a positive, they go away.

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Alternative MethodUse counters to add unlike signed integers.

-4 + 5

+

A positive and a negative together become neutral. When

we put a negative with a positive, they go away.

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Alternative MethodUse counters to add unlike signed integers.

-4 + 5

+

A positive and a negative together become neutral. When

we put a negative with a positive, they go away.

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Alternative MethodUse counters to add unlike signed integers.

-4 + 5

+

A positive and a negative together become neutral. When

we put a negative with a positive, they go away.

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Alternative MethodUse counters to add unlike signed integers.

-4 + 5

+

A positive and a negative together become neutral. When

we put a negative with a positive, they go away.

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Alternative MethodUse counters to add unlike signed integers.

-4 + 5

=

A positive and a negative together become neutral. When

we put a negative with a positive, they go away.

That leaves a positive

one as our answer. It

is the same answerthat we got using

strictly math.