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}#