How do you solve the following system?: $- 5 x - 4 y = 3, 3 x - y = - 2$ $-5x -4y =3, 3x -y = -2$

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How do you solve the following system?: $- 5 x - 4 y = 3, 3 x - y = - 2$ $-5x -4y =3, 3x -y = -2$

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Answer 1 · 2017-03-02T13:45:44

$x = - \frac{11}{17}$ $x=-11/17$ and $y = \frac{1}{17}$ $y=1/17$

Explanation:

$- 5 x - 4 y = 3$ $-5x-4y=3$
$3 x - y = - 2$ $3x-y=-2$

From the second equation, we can determine a temporary value for $y$ $y$ .

$3 x - y = - 2$ $3x-y=-2$

Add $y$ $y$ to each side.

$3 x = y - 2$ $3x=y-2$

Add $2$ $2$ to each side.

$3 x + 2 = y$ $3x+2=y$

In the first equation, substitute $y$ $y$ with $(3 x + 2)$ $color(red)((3x+2))$ .

$- 5 x - 4 y = 3$ $-5x-4y=3$

$- 5 x - 4 (3 x + 2) = 3$ $-5x-4color(red)((3x+2))=3$

Open the brackets ad simplify. The product of a negative and a positive is a negative.

$- 5 x - 12 x - 8 = 3$ $-5x-12x-8=3$

$- 17 x - 8 = 3$ $-17x-8=3$

Add $8$ $8$ to each side.

$- 17 x = 11$ $-17x=11$

Divide both sides by $- 17$ $-17$ .

$x = - \frac{11}{17}$ $x=-11/17$

In the second equation, substitute $x$ $x$ with $(- \frac{11}{17})$ $color(blue)((-11/17))$ .

$3 x - y = - 2$ $3x-y=-2$

$3 (- \frac{11}{17}) - y = - 2$ $3color(blue)((-11/17))-y=-2$

Open the brackets and simplify. The product of a positive and a negative is a negative.

$- \frac{33}{17} - y = - 2$ $-33/17-y=-2$

Add $y$ $y$ to each side.

$- \frac{33}{17} = y - 2$ $-33/17=y-2$

Add $2$ $2$ to each side.

$- \frac{33}{17} + 2 = y$ $-33/17+2=y$

$- \frac{33}{17} + (2 \times \frac{17}{17}) = y$ $-33/17+(2xx17/17)=y$

$- \frac{33}{17} + \frac{34}{17} = y$ $-33/17+34/17=y$

$\frac{- 33 + 34}{17} = y$ $(-33+34)/17=y$

$\frac{1}{17} = y$ $1/17=y$

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How do you solve the following system?: $- 5 x - 4 y = 3, 3 x - y = - 2$ $-5x -4y =3, 3x -y = -2$

1 Answer

Explanation:

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Impact of this question

Science

Math

Humanities

... and beyond

How do you solve the following system?: −5x−4y=3,3x−y=−2-5x -4y =3, 3x -y = -2

1 Answer

Explanation:

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Impact of this question

How do you solve the following system?: $- 5 x - 4 y = 3, 3 x - y = - 2$ $-5x -4y =3, 3x -y = -2$