SOLUTION: Solve using the square root property: (x+8)^2=81

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Question 184449: Solve using the square root property:
(x+8)^2=81
Found 3 solutions by stanbon, jim_thompson5910, josmiceli:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Solve using the square root property:
(x+8)^2=81
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x+8 = 9 or x+8 = -9
x = 1 or x = -17
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Cheers,
Stan H.

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

%28x%2B8%29%5E2=81 Start with the given equation.


x%2B8=0%2B-sqrt%2881%29 Take the square root of both sides.


x%2B8=sqrt%2881%29 or x%2B8=-sqrt%2881%29 Break up the "plus/minus" to form two equations.


x%2B8=9 or x%2B8=-9 Take the square root of 81 to get 9.


x=-8%2B9 or x=-8-9 Subtract 8 from both sides.


x=1 or x=-17 Combine like terms.


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Answer:


So the solutions are x=1 or x=-17.

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
%28x%2B8%29%5E2+=+81
Square roots come in pairs. There is a (+) and a (-)
square root.
Take the square root of both sides
x+%2B+8+=+9
x+=+1
and
x+%2B+8+=+-9
x+=+-17
The answers are x+=+1 and x+=+-17
check answers:
%28x%2B8%29%5E2+=+81
%281%2B8%29%5E2+=+81
81+=+81
and
%28-17%2B8%29%5E2+=+81
%28-9%29%5E2+=+81
81+=+81
OK