How do you solve the following system?: $-4x -3y =5, x -2y = -15$

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How do you solve the following system?: $-4x -3y =5, x -2y = -15$

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Answer 1 · 2018-05-17T13:30:54

$x = -5 and y = 5$

Explanation:

$-4x- 3y = 5 - - - eqn1$

$x - 2y = -15 - - - eqn2$

From the $eqn1$ rearrange the equation..

$-4x - 3y = 5$

Multiplying through by minus $(-)$ ;

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

$4x + 3y = -5 - - - eqn1$

Now solving simultaneously..

$4x + 3y = -5 - - - eqn1$

$x - 2y = -15 - - - eqn2$

Using Elimination Method..

Multiplying $eqn1$ by $1$ and $eqn2$ by $4$ respectively..

$1(4x + 3y = -5)$

$4(x - 2y = -15)$

$4x + 3y = -5 - - - eqn3$

$4x - 8y = -60 - - - eqn4$

Subtracting $eqn4$ from $eqn3$

$(4x - 4x) + (3y - (-8y) = -5 - (-60)$

$0 + 3y + 8y = -5 + 60$

$11y = 55$

$y = 55/11$

$y = 5$

Substituting the value of $y$ into $eqn2$

$x - 2y = -15 - - - eqn2$

$x - 2(5) = -15$

$x - 10 = -15$

$x = -15 + 10$

$x = -5$

Therefore;

$x = -5 and y = 5$

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How do you solve the following system?: $-4x -3y =5, x -2y = -15$

1 Answer

Explanation:

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Science

Math

Humanities

... and beyond

How do you solve the following system?: -4x -3y =5, x -2y = -15-4x -3y =5, x -2y = -15

1 Answer

Explanation:

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Impact of this question

How do you solve the following system?: $-4x -3y =5, x -2y = -15$