Y7 Math Adding Positive & Negative Integers_Sum In Operation 2

Adding integers with different signs

• Subtract and keep the sign of the LARGER number.

• Subtract and keep the number of the smaller signs.

• Adding integers is hard!

• Subtract and do not change the signs!

What sum does the set of tiles model?

yellow +

red -

• (+2) + (-3) = -1

• (+2) + (-3) = +1

• (-2) + (+3) = -1

• (-2) + (+3) = +1

What sum does the set of tiles model? Yellow is + and Red is -

• (+1) + (-4) = +3

• (+1) + (-4) = -3

• (-1) + (+4) = -3

• (-1) + (+4) = +3

Add.

5 + (-7)

• 12

• 2

• -2

• -12

2 + (-4 ) =

• -2
• 2
• 0
• -4

In addition if the signs are different (2)

• add

• subtract

• the sum is always positive

• the sum is always negative

• take sign of number with greater absolute value

Solve:

25 + -63

• 88

• -88

• 38

• -38

Will the sum of 50 + (-50) be a positive, negative, or zero?

• positive

• negative

• zero