The both equations should equal 180° when combined. So when you add like-terms you get 8x+20=180. X=20°
In order to solve the problem above, represent the width by x. With this, the length of the rectangular portrait is 1.5x. The perimeter of the rectangle is two times the sum of the length and width. This translates to,
2 (1.5x + x) = 10 ft, x = 2 ft.
Thus, the length of the rectangular portrait is 3 ft.
10 because -2 minus 12 is 10