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

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

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Answer 1 · 2015-12-24T20:47:19

$(- \frac{12}{7}, - \frac{3}{7})$ $(-12/7, -3/7)$

Explanation:

You can solve this system of equation by substitution

$y = 2 x + 3$ $color(red)(y = 2x +3$
$x + 3 y = - 3$ $x + 3y = -3$

Substitute $y = 2 x + 3$ $y =2x + 3$ into the second equation

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

Distribute and combine like terms

$x + 6 x + 9 = - 3$ $x + 6x + 9 = -3$

$7 x + 9 = - 3$ $7x + 9 = -3$
$7 x = - 3 - 9$ $7x = -3 -9$

$7 x = - 12$ $7x = -12$

$x = - \frac{12}{7}$ $x = -12/7$

Then re-substitute $x = - \frac{12}{7}$ $x = -12/7$ into $y = 2 x + 3$ $y= 2x+3$ to solve for $y$ $y$

$y = 2 (- \frac{12}{7}) + 3$ $y = 2( -12/7) + 3$
$\Rightarrow y = - \frac{24}{7} + \frac{21}{7}$ $=> y = -24/7 + 21/7$
$\Rightarrow y = - \frac{3}{7}$ $=> y = -3/7$

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

1 Answer

Explanation:

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Impact of this question

Science

Math

Humanities

... and beyond

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

1 Answer

Explanation:

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Impact of this question

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