Question

solve 4/x + 5/y=7; 3/x+4/y=5
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Answer 1

suppose 1/x as a 1/y as b

so eq =

4a+5b=7

3a+4b=5 then u can solve by 3 method

substitution , elimination , cross multiplication

Answer 2

$\frac{4}{x} + \frac{5}{y} = 7$

$\frac{3}{x} + \frac{4}{y} = 5$

we have to substitute the values from the above equations.

$\frac{4}{x} - \frac{3}{x} + \frac{5}{y} - \frac{4}{y} = 7 - 5$

$\frac{1}{x} + \frac{1}{y} = 2$

$\frac{y + x}{xy} = 2$

$y + x = 2xy$

Hope my answer to help you..