How do solve the following linear system?: $- 2 x - 8 y = 4, 3 x - y = 3$ $-2x -8y = 4 , 3x-y=3$ ?

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How do solve the following linear system?: $- 2 x - 8 y = 4, 3 x - y = 3$ $-2x -8y = 4 , 3x-y=3$ ?

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Answer 1 · 2016-01-10T12:15:27

$x = \frac{10}{13}, y = - \frac{9}{13}$ $x=10/13, y = -9/13$

Explanation:

To solve by elimination you will need to make coefficients of x or y "match" so that when you add or subtract the equations one of the variables will be eliminated.

If we multiply the second equation by 8 we get:
$- 2 x - 8 y = 4$ $-2x - 8y = 4$
$24 x - 8 y = 24$ $24x - 8y = 24$

Now if we subtract the two new equations, we will eliminate y and will be able to solve an equation in x.

$26 x = 20$ $26x = 20$
$x = \frac{10}{13}$ $x=10/13$

Substitute this back into one of the original equations to find y.

$3 \cdot \frac{10}{13} - y = 3$ $3*10/13 - y =3$
$\frac{30}{13} - y = 3$ $30/13 - y = 3$
$- y = \frac{9}{13}$ $-y=9/13$
$y = - \frac{9}{13}$ $y=-9/13$

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How do solve the following linear system?: $- 2 x - 8 y = 4, 3 x - y = 3$ $-2x -8y = 4 , 3x-y=3$ ?

1 Answer

Explanation:

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Science

Math

Humanities

... and beyond

How do solve the following linear system?: −2x−8y=4,3x−y=3 -2x -8y = 4 , 3x-y=3 ?

1 Answer

Explanation:

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How do solve the following linear system?: $- 2 x - 8 y = 4, 3 x - y = 3$ $-2x -8y = 4 , 3x-y=3$ ?