I am not sure what I suppose to do ​

put values of x in the equations above the boxes and write the answer in y column

I'm pretty sure that you need to subsitute the values for x into the equations. For example, if the equation is y=x-7, you should start by putting 2 in for x (y=2-7). This would mean that your answer is -5. Is that what you were asking?

gdp is the best phrase!

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