How do you solve $3 y - 2 x = 11$ $3y - 2x = 11$ and $y + 2 x = 9$ $y + 2x = 9$ using substitution?

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Answer 1 · 2018-03-10T04:44:17

$y = 5 and$ $y=5 and$ x=2#

$2 x + y = 9$ $2x + y =9$
$- 2 x + 3 y = 11$ $-2x + 3y =11$

We need to solve $2 x + y = 9$ $2x + y = 9$ for $y$ $y$

$2 x + y = 9$ $2x + y = 9$
$y = 9 - 2 x$ $y=9 -2x$

Now substitute $- 2 x + 9$ $-2x + 9$ for $y$ $y$ in $- 2 x + 3 y = 11$ $-2x + 3y =11$

$- 2 x + 3 y = 11$ $-2x + 3y =11$

$- 2 x + 3 (- 2 x + 9) = 11$ $-2x + 3(-2x+9)=11$

Distribute

$- 2 x + (3) (- 2 x) + (3) (9) = 11$ $-2x + (3)(-2x)+(3)(9)=11$

$- 2 x - 6 x + 27 = 11$ $-2x - 6x + 27 = 11$

$- 8 x + 27 = 11$ $-8x + 27 = 11$

$- 8 x = 11 - 27$ $-8x = 11 - 27$

$- 8 x = - 16$ $-8x = -16$

$x = \frac{- 16}{- 8}$ $x=(-16)/(-8)$

$x = 2$ $x=2$

Now substitute $2$ $2$ for $x$ $x$ in $y = - 2 x + 9$ $y=-2x+9$

$y = - 2 x + 9$ $y=-2x + 9$

$y = - 2 (2) + 9$ $y=-2(2)+9$

$y = - 4 + 9$ $y=-4 + 9$

$y = 5$ $y=5$

Thus,

The answers are $y = 5$ $y=5$ and $x = 2$ $x=2$

How do you solve 3y−2x=113y - 2x = 11 and y+2x=9y + 2x = 9 using substitution?