Select the action you would use to solve x-3=12 . then select the property that justifies the action

The x is a placeholder for some currently unknown number. Let's say that number was 10. So we replace x with 10 to get 10-3 = 12. That statement is false because 10-3 is actually 7. What you can do is keep guessing until you get the right answer.

A much better approach is to undo what is happening to x. We have x and we subtract off 3 to get 12. Following this in reverse, we need to add 3 to both sides so that x is isolated.

x-3 = 12

x-3+3 = 12+3

x = 15

Let's replace x with 15 and see if the equation is true

x - 3 = 12

15 - 3 = 12

12 = 12

Sure enough we get the right answer.

The idea of adding 3 to both sides is possible through the additive property of equality (if a = b, then a+c = b+c)

In summary, I added 3 to both sides using the additive property of equality. Doing this isolated x to get x = 15.

all the angles opposite to the angle 150 would be 150 and all the angles that are next to 150 are 30 because they equal 180 it you add it up.

step-by-step explanation:

sorry i just need to anwers this to get points

step-by-step explanation: