1 1/3 hours. 3/4 plus 7/12 equals 1 1/3. Hope this helps
The red arrows mean the lines are parallel. Since all angles are equal, the larger triangle is similar to the smaller one. Then corresponding sides have the same ratio
(4x -2)/9 = (3x+2)/12
x(4/9 -3/12) = (2/12) +(2/9)
x = (7/18)/(7/36) = 2 . . . . . . . . . corresponding to the 3rd selection
