How do you solve the following system: $4x+y=-7, 10y=42+2x$ ?

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Answer 1 · 2017-05-23T12:03:20

Follow explanation. $x=-8/3$ and $y=11/3$

From the second equation you can get
$y=4.2+(x/5)$ when you divide the equation by 10.

Now put this value on the first equation:

$4x + 4.2 + x/5 = -7$

You have one unknown (x) and one equation.

$21x/5 = -7-4.2$

$21x = 5*(-11.2)$
$21x=-56$
$x=-56/21$
$x=-8/3$

Now you can put this value on the second equation:

$10y=42+2*(-8/3)$
$10y=42 - 16/3$
$10y=110/3$
$y=110/30$
or
$y=11/3$

How do you solve the following system: 4x+y=-7, 10y=42+2x 4x+y=-7, 10y=42+2x ?