How do you find five ordered pairs of $x + 2 y = 8$ $x+2y=8$ ?

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Answer 1 · 2016-08-08T19:07:42

$(6, 1), (- 4, 6)$ $(6,1), (-4,6)$ and so on .....
Infinitely many pairs can be found.

Change the equation around to have $y$ $y$ as the subject.

$x + 2 y = 8$ $x + 2y = 8$

$2 y = 8 - x y = 4 - \frac{x}{2}$ $2y = 8-x" " y = 4-x/2$

Now choose any value of $x$ $x$ , (even numbers will be easier to work with), and calculate the corresponding value of $y$ $y$

If $x = 6, y = 4 - \frac{6}{2} = 4 - 3 = 1 \Rightarrow (6, 1)$ $x =6, y = 4-6/2 = 4-3 = 1" "rArr (6,1)$

If $x = - 4, y = 4 - \frac{- 4}{2} = 4 + 2 = 6 \Rightarrow (- 4, 6)$ $x =-4, y = 4-(-4)/2 = 4+2 = 6" "rArr (-4,6)$

And so on ... choose $x$ $x$ -values and find $y$ $y$ -values.

How do you find five ordered pairs of x+2y=8x+2y=8x+2y=8?