What are x and y if $x + y = 4$ $x+y=4$ and $y = - 7 x + 4$ $y=-7x+4$ ?

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What are x and y if $x + y = 4$ $x+y=4$ and $y = - 7 x + 4$ $y=-7x+4$ ?

1 Answer

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Answer 1 · 2018-04-11T08:32:03

Please look below.

Explanation:

$x + y = 4$ $x + y = 4$ ---(1)

$y = - 7 x + 4$ $y = -7x + 4$ ---(2)

The $x$ $x$ s and $y$ $y$ s in the question are of the same value. This means that you can substitute the value of $y$ $y$ in the second equation into the first equation:

$x + (- 7 x + 4) = 4$ $x + (-7x +4) = 4$

This allows you to find $x$ $x$ :

$x - 7 x + 4 = 4$ $x-7x + 4 = 4$

$- 6 x = 0$ $-6x = 0$

$x = 0$ $x = 0$

Then this value can be substituted into either of the given equations:

$0 + y = 4$ $0 + y = 4$

$y = 4$ $y = 4$

So $x = 0$ $x = 0$ and $y = 4$ $y = 4$ .

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What are x and y if $x + y = 4$ $x+y=4$ and $y = - 7 x + 4$ $y=-7x+4$ ?

1 Answer

Explanation:

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What are x and y if x+y=4x+y=4x+y=4 and y=-7x+4y=−7x+4y=-7x+4?

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Explanation:

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What are x and y if $x + y = 4$ $x+y=4$ and $y = - 7 x + 4$ $y=-7x+4$ ?