So you want to add 7x degrees and (x-4) degrees. And it will be 8x - 4 = 180 degrees because it's 180 degrees in a straight line. And you want to + the 180 by 4 because there is -4 on the other side. so it will be 8x = 184 and you just divide 184 by 8 and it will be 23 easy. if you want to my help again you can text me on instargram jason_lee093
