How do solve the following linear system?: $3 x + 4 y = - 2, x - 3 y = 1$ $3x + 4y = -2 , x - 3y = 1$ ?

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How do solve the following linear system?: $3 x + 4 y = - 2, x - 3 y = 1$ $3x + 4y = -2 , x - 3y = 1$ ?

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Answer 1 · 2016-05-25T06:10:28

$x = - 2$ $x=-2$
$y = 1$ $y=1$

Explanation:

$3 x + 4 y = - 2 (1)$ $3x+4y=-2" (1)"$
$- 2 x - 3 y = 1 (2)$ $-2x-3y=1" (2)"$

$expand both sides of equation (1) by 2;$ $"expand both sides of equation (1) by 2;"$
$6 x + 8 y = - 4$ $6x+8y=-4$
$rearranging the equation : 6 x = - 4 - 8 y (3)$ $"rearranging the equation :" 6x=-4-8y" "(3)$

$expand both sides of equation 2 by 3;$ $"expand both sides of equation 2 by 3;"$
$- 6 x - 9 y = 3$ $-6x-9y=3$
$rearranging the equation : 6 x = - 9 y - 3 (4)$ $"rearranging the equation :"6x=-9y-3" "(4)$

$Both ;the left sides of equations (3) and (4) are equal$ $"Both ;the left sides of equations (3) and (4) are equal"$

$6 x = - 4 - 8 y$ $color(red)(6x)=-4-8y$
$6 x = - 9 y - 3$ $color(red)(6x)=-9y-3$

$The right sides of equations can be written as equal$ $"The right sides of equations can be written as equal"$

$- 4 - 8 y = - 9 y - 3$ $-4-8y=-9y-3$

$9 y - 8 y = - 3 + 4$ $9y-8y=-3+4$

$y = 1$ $y=1$

$now use (1) or (2)$ $"now use (1) or (2)"$

$3 x + 4 \cdot 1 = - 2$ $3x+4*1=-2$
$3 x + 4 = - 2$ $3x+4=-2$
$3 x = - 6$ $3x=-6$
$x = - \frac{6}{3}$ $x=-6/3$
$x = - 2$ $x=-2$

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How do solve the following linear system?: $3 x + 4 y = - 2, x - 3 y = 1$ $3x + 4y = -2 , x - 3y = 1$ ?

1 Answer

Explanation:

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Science

Math

Humanities

... and beyond

How do solve the following linear system?: 3x+4y=−2,x−3y=1 3x + 4y = -2 , x - 3y = 1 ?

1 Answer

Explanation:

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Impact of this question

How do solve the following linear system?: $3 x + 4 y = - 2, x - 3 y = 1$ $3x + 4y = -2 , x - 3y = 1$ ?