Lesson 2-4

When adding positives: Add numbers Sign is positive Examples:

When adding two negatives: Get rid of the double sign. Add together how many “negatives you have”. Examples -2+(-3)-4+(-4)-1+(-8)

When adding opposite signs: If there is a “double sign”, get rid of it (SOO). See if you have more “positives” or more negatives. Take the sign you have more of, and subtract the number you have less of. Your answer takes the sign of the one you have more of. (I’ll explain this in class) Exmples: (-2)

Positive + Positive = ____________ Negative + Negative = _______________ Positive + Negative = ________________ Negative + Positive = _______________

8 – – 7

1 – (-2) -10 – (-7)

4 – (-12)-15 – (-5)

Replace the variable with its value and solve.

a = 5 b = -8 c = -9 b – 10a – b c – a

abcdef -5

Number Trail