### Home > CC3 > Chapter 1 > Lesson 1.1.4 > Problem1-34

1-34.

Compute without using a calculator. Homework Help ✎

1. $−15+7$

Try thinking of the problem as $7−15$.

$−8$

1. $8−(−21)$

Remember that subtracting a negative number is the same as adding a positive number.

Read the problem as $8+21$.

1. $6(−8)$

A positive multiplied by a negative equals a negative.

$−48$

1. $−9+(−13)$

Both numbers have a negative sign in front of them. Add them and keep the negative sign.

1. $−50−30$

$−80$

1. $3−(−9)$

See the hint for part (a).

1. $−75−(−75)$

See the hint for part (b).

$−75−(−75)=−75+75=0$

1. $(−3)+6$

$6−3$.

1. $9+(−14)$

What if the question were $14−9$?

$−5$

1. $28−(−2)$

See the hint for part (b).

$28−(−2)=28+2=30$

1. $−3+(−2)+5$

It may be easier to compute this in more than one step.

Because the only operations are addition and subtraction, the order in which they are carried out does not matter.

1. $3+2+5$

See the hint for part (k).