How do you solve the system $y = 2 - x$ $y=2-x$ and $5 = y + 2 x$ $5=y+2x$ using substitution?

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Answer 1 · 2015-05-21T08:00:38

$y = 2 - x$ $y=2-x$ --------------(1)

$5 = y + 2 x$ $5=y+2x$ ---------------(2)

Substituting $y$ $y$ from the first equation into the second one gives us:

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

$5 = 2 - x + 2 x$ $5 = 2 - x + 2x$

$5 = 2 + x$ $5 = 2 + x$

Transposing 2 to the left hand side gives us :

$5 - 2 = x$ $5-2 = x$

$x = 3$ $color(green)(x = 3$

Substituting $x = 3$ $x = 3$ in the first equation will give us :

$y = 2 - 3$ $y = 2 - 3$

$y = - 1$ $color(green)(y = -1$

The solution to both these equations : $x = 3; y = - 1$ $x = 3; y = -1$

Verify :

Substitute the values of $x and y$ $x and y$ in both the equations to see if they are satisfied

How do you solve the system y=2−xy=2-x and 5=y+2x5=y+2x using substitution?