WHAT PROPERTY IS 12.2+18.6+-4.3+(18.6)

it has to be 45.1.

Step-by-step explanation:

The reason why its 45.1 is because I added the equation all together including the negative number. I out that one in parentheses right next to the plus sign of 18.6. then added the last 2 numbers. and get 45.1. I'm not really good with stop by step explanations to be honest.

:(

i think it is everything has to equal 180 so, if i correct 4=c. 6=d. 8=a. 7=b. and the last question would be c. because they are parallel lines and they are congruent.

step-by-step explanation:

the reason everything has to equal to 180 is because that is how it works. i'm guessing that is its rule. 4 and 8 are congruent and parallel so, that would be 30+30 because they have the same number. it would equal 60. 6 and 7 are congruent and parallel so, that would be 30+30 because they have the same number. it would equal 60. 60+60 is 180. so, now you have your answer