How do you solve by substitution $y=-4x+8$ and $y=x+7$ ?

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Answer 1 · 2018-03-26T20:26:17

$x = 1/5$

You have 2 expressions for y. $y = -4x + 8 and y = x+7$ .

The second expression tells us that y is equal to $x+7$ . Let's substitute $x+7$ for the y in the first expression. That will give us

$x+7 = -4x + 8$

And now, let's simplify.

$x+4x = 8 - 7$

$5x = 1$

Therefore, $x = 1/5$ .

I hope this helps,
Steve

How do you solve by substitution y=-4x+8y=-4x+8 and y=x+7y=x+7?