Answer:
c = -1
Step-by-step explanation:
3(c+5)=12
3 × c = 3c
3 × 5 = 15
3c + 15 = 12
<u> - 15 -15</u>
3c = -3
c = -3 ÷ 3 = -1
Check:
3(-1+5)=12
-3 + 15 = 12
The first box should be correct
30 + c = 40
The values that make this statement falser are any in which a and b do not have the same sign.
For instance, if a was equal to 3 and b was equal to -3 than see the results.
|a+b|=
|3+-3|=
|0|= 0
Then see the next equation with the same selections
|a|+|b|
|3|+|-3|
3 + 3 = 6
And this would be true no matter which is the negative, as long as there is one negative and one positive.
Answer:
Yes. In general, the set of rational numbers is closed under addition, subtraction, and multiplication; and the set of rational numbers without zero is closed under division.
Step-by-step explanation:
:)