Question

Știind ca x/y=7/9,determinați valoarea raportului 5x+2y/2x-y.

Answer 1

x/y=7/9, deci x = 7y/9

$\frac{5x+2y}{2x-y} =\frac{5*\frac{7y}{9} +2y}{2*\frac{7y}{9} -y} = \frac{\frac{35y+18y}{9} }{\frac{14y-9y}{9}}$$= \frac{\frac{53y}{9} }{\frac{5y}{9} } = \frac{53y}{9} * \frac{9}{5y} =\frac{53}{5}$

raspunsul este 53/5