Maths Olympiad Prep

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Algebra Difficulty 1.6 Junior Find the answer

If x0x\not=0 or 44 and y0y\not=0 or 66, then 2x+3y=12\frac{2}{x}+\frac{3}{y}=\frac{1}{2} is equivalent to

Pick one

Solution

To clear out the fractions, we multiply both sides of the equation by xyxy to get 2y+3x=xy22y+3x=\frac{xy}{2}, or 4y+6x=xy4y+6x=xy. From this, we have 4y=xy6x4y=xy-6x. We can factor an xx out of the RHS, and so 4y=x(y6)    4yy6=x,D4y=x(y-6)\implies \frac{4y}{y-6}=x, \boxed{\text{D}}.

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Source: NuminaMath-1.5, licensed Apache-2.0. Statement and solution reproduced as published; topic and difficulty added by this site.