how to solve equations with squares on both sides?

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by simplyjat » Fri Mar 14, 2008 10:14 pm
When you have to take square root, always consider both positive and negative factors in consideration
Whereas when you are given a square root you can assume it to be positive only...
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by musicdaemon » Sat Mar 15, 2008 12:03 am
The Degree of variable x must be made same on each side,reduce the equation to basic form, then you can proceed with the solution as you would for a simple quadratic equation:

i.e.
(x+1)^2= x^2
=> x^2+2x+1 = x^2.................. (now you can cancel x^2 both sides)
=> 2x+1=0
=> x= -1/2...................................Ans


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for sure you can take sqrt both side but thats gonna get you to |x+1| = |x| and if you are not lost with that it's ok to go ahead, otherwise just do the calculations in the previous post ;)
netigen wrote:for e.g.

(x+1)^2 = x^2

can we take sqrt both sides and safely say x+1 = x? doesn't sound right to me.