Triangle ABC is similar to Triangle XYZ. This means that AB/BC = XY/YZ is one proportion we can form
Plug in the given expressions and then isolate x AB/BC = XY/YZ (5x+25)/(7x+44) = 14/29 29(5x+25) = 14(7x+44) 29(5x)+29(25) = 14(7x)+14(44) 145x+725 = 98x+616 145x-98x = 616-725 47x = -109 x = -109/47
note: its possible your teacher made a typo since we got a negative fraction here. I would ask your teacher to double check.
