SOLUTION: My problem is to use the quadratic equation for: (r-3)(r+9)=16. I'm up to the step where r equals pus or minus the square root of 208 divide by 2. At this point I'm not sure how to

Question 593408: My problem is to use the quadratic equation for: (r-3)(r+9)=16. I'm up to the step where r equals pus or minus the square root of 208 divide by 2. At this point I'm not sure how to factor out the next three steps to get the solution step. My answer came out to be {-3+2 square root over 2 , -3-2 square root over 2}
I did my best here to describe the symbols that I can't enter in this example. Thanks, James
Found 2 solutions by ankor@dixie-net.com, Earlsdon:
Answer by ankor@dixie-net.com(22740) (Show Source): You can put this solution on YOUR website!
My problem is to use the quadratic equation for: (r-3)(r+9)=16.
FOIL
r^2 + 9r - 3r - 27 = 16
r^2 + 6x - 27 - 16 = 0
r^2 + 6x - 43 = 0
Use the quadratic formula

x=r, a=1, b=6, c=-43

:

:

I think here you went astray somewhere
Factor inside the radical to reveal a perfect square

Extract the square root of 16

Two solutions

and

Answer by Earlsdon(6294) (Show Source): You can put this solution on YOUR website!
Solve:
Simplify.
Subtract 16 from bothsides.
Solve using the quadratic formula.
Simplify.

or
or
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