Question #080e7

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Answer 1 · 2017-03-10T00:27:03

$x = 11$ ; $y = 87$

Given:
$y=x^2−3x−1$
$y=8x−1$

Since both of these equations on the right side are equal to $y$ on the left side we can merge these two equations into:

$x^2−3x−1=8x−1$

Then, combine like terms:

$x^2=11x$

Divide each side by x, and you get $x=11$

You will need to continue on to solve for $y$ by inserting your value for $x$ into either of the $given$ equations:

$y = 8x -1$
$y = 8(11) - 1$
$y = 88 -1$
$y = 87$

From here you can check your answer by substituting both of your values into the other $given$ equation:

$y = x^2 - 3 x - 1$
$(87) = (11)^2 -3(11) -1$
$87 = 121 -33 -1$
87 = 87