How do you solve the system by substitution for $–4.5x -2y=– 12.5$ and $3.25x – y=– 0.75$ ?

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Answer 1 · 2015-03-28T10:35:53

The answer is:

$x=1$
$y=4$ .

Because:

$–4.5x -2y=– 12.5$
$3.25x – y=– 0.75$

Form the second equation, let's find $y$ , than let's substitue in the first:

$y=3.25x+0.75$

and so:

$-4.5x-2*(3.25x+0.75)=-12.5rArr$

$-4.5x-6.50x-1.5=-12.5rArr-11x=-11rArrx=1$ .

And now let's go back:

$y=3.25*1+0.75rArry=4$ .

How do you solve the system by substitution for –4.5x -2y=– 12.5–4.5x -2y=– 12.5 and 3.25x – y=– 0.753.25x – y=– 0.75?