Factor out the common factor of 2x from
14x^(3/5) * 16x^(1/2)
The first step will be to multiply the two factors:
$\displaystyle 14x^{\frac{3}{5}}\, \times\, 16x^{\frac{1}{2}}\, =\, 14\times 16\times x^{\frac{3}{5}\, +\, \frac{1}{2}}\, =\, 224x^{\frac{11}{10}}$
You can then factor out 224x (or just the specified 2x), leaving behind one tenth-root of x, times whatever you didn't factor out.
This seems a very odd exercise....