500,883 views
39 votes
39 votes
___ +(-9)=-12 need help please

User Roly
by
2.6k points

2 Answers

12 votes
12 votes

Answer:

_-3__ + (-9) = -12

Explanation:

___ + (-9) = -12

-9 is being added to the blank. You want the blank alone (isolated) on the left side. The opposite operation to adding a -9 is to add a positive 9.

You must do the same operation to both sides of an equation.

Add 9 to both sides.

___ + (-9) + 9 = -12 + 9

___ + 0 = -3

___ = -3

Answer: -3

User DontGoPlastic
by
3.1k points
18 votes
18 votes

Answer:

-3

Explanation:

Hi there!

___ + (-9) = -12

Adding a negative number is the same as subtracting

___ - 9 = -12

To isolate the blank, we can add 9 to both sides of the equal sign so there won't be a -9 on the left side

___ - 9 + 9 = -12 + 9

___ = -12 + 9

___ = -3

Therefore, the number is -3.

I hope this helps!

User Simon Kocurek
by
2.7k points