Question
For solving pair of equation, in this exercise use the method of elimination by equating coefficients $:13 + 2y = 9x,3y = 7x$
✓
Answer
$13+2 y=9 x\ldots(1)$
$3 y=7 x\ldots(2)$
Multiplying equation no.$ (1)$ by $ 3$ and $(2)$ by $2$ , we get,
$39+6 y =27x\dots(1)$
$6 y =14x\dots(2)$
$39 =13x$
$x =3$
From $(2)$
$ 3 y=7 x$
$ \therefore 3 y=7(3)$
$ \therefore y=\frac{21}{3}$
$=7$
$3 y=7 x\ldots(2)$
Multiplying equation no.$ (1)$ by $ 3$ and $(2)$ by $2$ , we get,
$39+6 y =27x\dots(1)$
$6 y =14x\dots(2)$
$39 =13x$
$x =3$
From $(2)$
$ 3 y=7 x$
$ \therefore 3 y=7(3)$
$ \therefore y=\frac{21}{3}$
$=7$
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