SOLUTION: Find all solutions of the equation |x^2 - 14x + 29| = 4.

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Question 1044821: Find all solutions of the equation |x^2 - 14x + 29| = 4.
Found 2 solutions by ikleyn, Boreal:
Answer by ikleyn(52810) About Me  (Show Source):
You can put this solution on YOUR website!
.
Find all solutions of the equation |x^2 - 14x + 29| = 4.
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This equation deploys in two independent equations:

1)  x%5E2+-+14x+%2B+29 = 4  --->  x%5E2+-+14x+%2B+25 = 0  --->  x%5B1%2C2%5D = %2814+%2B-+sqrt%2896%29%29%2F2;

                                                       x%5B1%5D = 7+%2B+2sqrt%286%29,  x%5B2%5D = 7+-+2sqrt%286%29. 

and 

2)  x%5E2+-+14x+%2B+29 = -4  --->  x%5E2+-+14x+%2B+33 = 0 ---> (x-11)*(x-3) = 0  --->  x = 11  or  x = 3.


Answer.  x%5B1%5D = 7+%2B+2sqrt%286%29,  x%5B2%5D = 7+-+2sqrt%286%29,  x%5B3%5D = 11  and  x%5B4%5D = 3. 




Plots y = |x^2 - 14x + 29| and y = 4.

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    - HOW TO solve equations containing Quadratic Terms under the Absolute Value sign. Lesson 2
in this site.


Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
|x^2 - 14x + 29| = 4.
start with x^2-14x+29=4
x^2-14x+25=0
x=(1/2)(14+/- sqrt (196-100); sqrt 96=4 sqrt (6)
x=7+2 sqrt (6) and 7-2 sqrt (6). Numerically, these are about 11.9 and 2.1
Check and 11.9 and 2.1 are both within 0.01 (rounding error).
graph%28300%2C300%2C-10%2C15%2C-10%2C10%2Cx%5E2-14x%2B25%29
The other solution is when x^2-14x+29=-4, because |-4|=4.
Now x^2-14x+33=0
(x-11)(x-3)=0
x=11,3
Check in the original |121-154+29|=|-4)=4; 9-42+29=|-4|=4
graph%28300%2C300%2C-10%2C15%2C-10%2C10%2Cx%5E2-14x%2B33%29
Exact solutions are 7-2 sqrt(6),3,11, and 7+2 sqrt (6)