Answer:
Triangle HBN ~ triangle LYR
=> HN/LR = HB/LY
=> (3x - 7)/(x + 11) = 28/21
=> 21(3x - 7) = 28(x + 11)
=> 63x -147 = 28x + 308
=> 35x = 455
=> x = 455/35 = 13
There is no answer to select. But I still believe there is no mistake in my calculation.
Hope this helps!
:)