SOLUTION: solving equations by completing the square. p^2+16p-22=0 I can't seem to come up with two factors that work.

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Question 818423: solving equations by completing the square.
p^2+16p-22=0
I can't seem to come up with two factors that work.

Found 2 solutions by Alan3354, Edwin McCravy:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
solving equations by completing the square.
p^2+16p-22=0
I can't seem to come up with two factors that work.
==============
That's because it can't be factored.
Complete the square.
p^2+16p-22=0
p^2+16p = 22
p^2+16p+64 = 86
(p+8)^2 = 86
p%2B8+=+sqrt%2886%29
etc

Answer by Edwin McCravy(20054) About Me  (Show Source):
You can put this solution on YOUR website!
solving equations by completing the square.
p^2+16p-22=0
I can't seem to come up with two factors that work.
Of course you can't seem to come up with two factors
that work.  There ARE NONE!  :)

That's why they told you to COMPLETE THE SQUARE instead.

Completing the square is what you have to do when the
quadratic cannot be factored.

p²+16p-22 = 0

Isolate the variable terms by adding 22 to both sides:

   p²+16p = 22

Multiply the coefficient of p, which is 16, by 1%2F2 getting
16·1%2F2 = 8.  Then square 8, getting 64.  Add 64 to both sides 
of the equation.

p²+16p+64 = 22+64

Now the left side will factor.  Combine the numbers on the right:

(p+8)(p+8) = 86

Note that the left side has factored a special way.  Both factors are
the same, so we can write:

    (p+8)² = 86

Now we take square roots of both sides:

   √(p+8)² = ±√86

       p+8 = ±√86
   
         p = -8±√86

So there are two solutions:

Using the +:   p = -8+√86
 which is approximately 1.273618495

Using the -:   p = -8-√86 
which is approximately -17.2736185

Edwin