How do you find the solution of the system of equations $2 x - y = - 1$ $2x-y=-1$ and $3 x + 2 y = - 5$ $3x+2y=-5$ ?

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Answer 1 · 2015-05-18T21:38:58

You an isolate one variable in one equation and then substitute its value in the other equation, as follows:

Let's isolate $y$ $y$ in the first one.

$y = 2 x + 1$ $y=2x+1$

Now, substituting in the second:

$3 x + 2 (2 x + 1) = - 5$ $3x+2(2x+1)=-5$

$3 x + 4 x + 2 = - 5$ $3x+4x+2=-5$
$7 x = - 7$ $7x=-7$
$x = - 1$ $x=-1$

If $x = - 1$ $x=-1$ and $y = 2 x + 1$ $y=2x+1$ , then $y = 2 (- 1) + 1 = - 1$ $y=2(-1)+1=-1$ .

Then, $x = y = - 1$ $x=y=-1$

How do you find the solution of the system of equations 2x-y=-12x−y=−12x-y=-1 and 3x+2y=-53x+2y=−53x+2y=-5?