Answer:
18
Explanation:
Now on here it has been a while since I did this so I am not sure this is the correct name, but I believe these are called complimentary angles, but I'm not 100% sure on that.
What I do know is that because f and g are parallel, that the measures of the angles will add up to be 180 degrees. So in this case I would try plugging in the answer choices and whichever one allows the equations to add up to 180 degrees is the answer. If you had to you could set it up to where you do the first equation plus the second equals 180 and then solve for x, but in this case we have answer choices so we will use them.
In this case I plugged in 18 first because it is in the middle of 19 and 17 so I would know from there whether to go up or down. I also noticed there was a -18 so I assumed 18 would be a good guess. When I plugged in 18 to the first equation I got 54. When I plugged 18 into the second equation I got 126. I added up the two numbers and got 180 telling me that the answer is 18.
Hope this helps!
