Question

x+2y=10, 5x+7y=15 find x and y​

Answer 1

$given$

$x + 2y = 10$

$5x + 7y = 15$

$now$

$using \: elimination \: method$

$x + 2y = 10 \times 7 \\ 5x + 7y = 15 \times 2$

$7x + 14y = 70 \\ - \: 10x + 14y = 30 \\ - - - - - - - - - - \\ - 3x = 40$

$x = \frac{40}{3}$

$putting \: the \: value \: of \: x \: in \\ x + 2y = 10$

$\frac{ - 40}{3} + 2y = 10$

$2y = 10 + \frac{40}{3}$

$2y = \frac{30 + 40}{3}$

$6y = 70$

$y = \frac{70}{6}$

$y = \frac{35}{3}$