Question
Solve for $x$ and $y:$
$2x - y + 3 = 0,$
$3x - 7y + 10 = 0$
$2x - y + 3 = 0,$
$3x - 7y + 10 = 0$
✓
Answer
$2x - y + 3 = 0$
$⇒ 2x - y = - 3 ...(i)$
$3x - 7y + 10 = 0$
$⇒ 3x - 7y = 10 ...(ii)$
Multiply $(i)$ by $-7$ and add it to $(ii).$
$-14x + 7y = 21$ and $3x - 7y = -10$
$⇒ -11x = 11$
$⇒ x = -1$
Substituting $x = 1$ in $(i),$ we get $y = 1$
So, $x = -1$ and $y = 1$
$⇒ 2x - y = - 3 ...(i)$
$3x - 7y + 10 = 0$
$⇒ 3x - 7y = 10 ...(ii)$
Multiply $(i)$ by $-7$ and add it to $(ii).$
$-14x + 7y = 21$ and $3x - 7y = -10$
$⇒ -11x = 11$
$⇒ x = -1$
Substituting $x = 1$ in $(i),$ we get $y = 1$
So, $x = -1$ and $y = 1$
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