How do solve the following linear system?: $2 x + 6 y = 5, - x - y = 8$ $2x+6y=5 , -x - y = 8$ ?

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How do solve the following linear system?: $2 x + 6 y = 5, - x - y = 8$ $2x+6y=5 , -x - y = 8$ ?

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Answer 1 · 2017-02-16T06:47:46

$x = - \frac{53}{4}$ $x=-53/4$ and $y = \frac{21}{4}$ $y=21/4$

Explanation:

We have two equations here

$2 x + 6 y = 5$ $2x+6y=5$ **......................(1) and

$- x - y = 8$ $-x-y=8$ **......................(2)

Observe that we have $2 x$ $2x$ in first equation and $- x$ $-x$ in second equation. So if we double (2) and add to (1), $x$ $x$ will be eliminated and we get

$2 x + 6 y - 2 x - 2 y = 5 + 16$ $2x+6y-2x-2y=5+16$ or $4 y = 21$ $4y=21$ i.e. $y = \frac{21}{4}$ $y=21/4$

putting this value in (2), we get

$- x - \frac{21}{4} = 8$ $-x-21/4=8$ or $- x = 8 + \frac{21}{4} = \frac{32 + 21}{4} = \frac{53}{4}$ $-x=8+21/4=(32+21)/4=53/4$

and $x = - \frac{53}{4}$ $x=-53/4$

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How do solve the following linear system?: $2 x + 6 y = 5, - x - y = 8$ $2x+6y=5 , -x - y = 8$ ?

1 Answer

Explanation:

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Science

Math

Humanities

... and beyond

How do solve the following linear system?: 2x+6y=5,−x−y=8 2x+6y=5 , -x - y = 8 ?

1 Answer

Explanation:

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Impact of this question

How do solve the following linear system?: $2 x + 6 y = 5, - x - y = 8$ $2x+6y=5 , -x - y = 8$ ?