How do solve the following linear system?: $x - 4 y = 2, x - 7 y = 4$ $x-4y=2 , x-7y=4$ ?

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Answer 1 · 2015-12-28T17:09:44

$(- \frac{2}{3}, - \frac{2}{3})$ $(-2/3,-2/3)$

Try to leave $x$ $x$ alone in one side of the equation, then equate the other sides;

$x = 2 + 4 y, x = 4 + 7 y$ $x=2+4y , x=4+7y$

$2 + 4 y = 4 + 7 y$ $2+4y=4+7y$ $\to$ $->$ $- 3 y = 2$ $-3y=2$
$y = - \frac{2}{3}$ $y=-2/3$

Now, write $- \frac{2}{3}$ $-2/3$ instead of $y$ $y$ in one of the equations, the value of $x$ $x$ will be the same for both of them.

$x = 2 + 4 . (- \frac{2}{3})$ $x=2+4.(-2/3)$ $\to$ $->$ $x = 2 - \frac{8}{3}$ $x=2-8/3$
$x = - \frac{2}{3}$ $x=-2/3$

How do solve the following linear system?: x−4y=2,x−7y=4 x-4y=2 , x-7y=4 ?