How do you solve $4x - 8y = 30$ and $6x - 12y = -64$ ?

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Answer 1 · 2016-07-30T16:39:15

There is no solution.

First simplify each of the equations.

$4x - 8y = 30" " and " "6x - 12y = -64$

$2x -4y = 15" A "$
$x - 2y = -16 " B"$

Notice what happens if we multiply B by 2:

$2x - 4y = -32 " B"$

We have a contradiction!

In A $" "2x -4y = 15$

The left sides of A and B are the same, but they are equal to different numbers.

These equations cannot be solved to give a unique answer.
There is no solution.

How do you solve 4x - 8y = 304x - 8y = 30 and 6x - 12y = -646x - 12y = -64?