Question
Solve $:x+ y = 7xy,2x - 3y = - xy$
✓
Answer
$x+y=7 x y\ldots(1)$
$2 x-3=-x y\ldots(2)$
Multiplying equation no.$(1)$ by $3.$
$3 x+3 y=21 x y\ldots .(3)$
Adding equation $(3)$ and $(2)$
gathered
$3 x+3 y=21 x y+ 2 x-3 y=-x y-5 x=20 x y$
$y=\frac{1}{4}$
gathered From $(1)$
$\mathrm{x}+\frac{1}{4}=7 x\left(\frac{1}{4}\right)$
$\frac{1}{4}=\frac{3}{4} x$
$x=\frac{1}{3}$
$2 x-3=-x y\ldots(2)$
Multiplying equation no.$(1)$ by $3.$
$3 x+3 y=21 x y\ldots .(3)$
Adding equation $(3)$ and $(2)$
gathered
$3 x+3 y=21 x y+ 2 x-3 y=-x y-5 x=20 x y$
$y=\frac{1}{4}$
gathered From $(1)$
$\mathrm{x}+\frac{1}{4}=7 x\left(\frac{1}{4}\right)$
$\frac{1}{4}=\frac{3}{4} x$
$x=\frac{1}{3}$
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