How do you solve $y^2-7y-18=0$ ?

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Answer 1 · 2018-05-21T12:24:14

See a solution process below:

We can factor the left side of the equation as:

$(y - 9)(y + 2) = 0$

Now, we can equate each term on the left to $0$ and solve for $y$ :

Solution 1:

$y - 9 = 0$

$y - 9 + color(red)(9) = 0 + color(red)(9)$

$y - 0 = 9$

$y = 9$

Solution 2:

$y + 2 = 0$

$y + 2 - color(red)(2) = 0 - color(red)(2)$

$y + 0 = -2$

$y = -2$

The Solution Is: $y = {-2, 9}$

How do you solve y^2-7y-18=0y^2-7y-18=0?