How do solve the following linear system?: $3x-2y=2 , -4x-14y=28$ ?

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Answer 1 · 2016-02-02T14:01:31

Solve by substitution and elimination:

$3x-2y=2$

$-4x-14y=28$

We can eliminate $-14y$ from the second equation by $-2y$ from the first equation if we multiply it with $-7$ to get $14y$

$rarr-7(3x-2y=2)$

Use distributive property:

$rarr-21x+14y=-14$

Add both equations:

$rarr(-4x-14y=28)+(-21x+14y=-14)$

$rarr-25x=14$

$rarrx=-14/25$

Substitute the value of $x$ to the first equation:

$rarr3(-14/25)-2y=2$

$rarr-42/25-2y=2$

$rarr-2y=2+42/25$

$rarr-2y=92/25$

$rarry=92/25-:(-2/1)$

$rarry=92/25*(-1/2)$

$rarry=-46/25$

So,
$(x,y)=(-14/25,-46/25)$ :)

How do solve the following linear system?: 3x-2y=2 , -4x-14y=28 3x-2y=2 , -4x-14y=28 ?