SOLUTION: ______ √7x + 29 = x + 3

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Question 150473: ______
√7x + 29 = x + 3

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
sqrt%287x%2B29%29 = x + 3
:
Square both sides, this gets rid of the radical on the left
7x + 29 = (x+3)^2
:
FOIL (x+3)(x+3)
7x + 29 = x^2 + 6x + 9
:
0 = x^2 + 6x - 7x + 9 - 29
:
A quadratic equation:
x^2 - x - 20 = 0
:
Factors to:
(x-5)(x+4) = 0
:
The positive solution
x = 5
:
Check in the original equation
sqrt%287%285%29%2B29%29 = 5 + 3
sqrt%2864%29 = 8
:
The negative solution
x = -4
Check in original equation
sqrt%287%28-4%29%2B29%29 = -4 + 3
sqrt%28-28%2B29%29 = -1
sqrt%281%29 = -1
+1 does not = -1
:
Only x=5 is a solution