kycats2003
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How do I solve this problem:
sqrt x+4 - sqrt x-4 = 2
sqrt x+4 - sqrt x-4 = 2
College algebra
- Thread starter kycats2003
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- Apr 12, 2005
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Domain Issues are FIRSTkycats2003 said:
x >= -4 - Why is that?
Isolate one of the radicals
sqrt x+4 = 2 + sqrt(x-4)
Square things
x+4 = (2 + sqrt(x-4))<sup>2</sup>
Expand and Simplify. This will leave you still with a radical expression. Isolate it and square things again. It is a bit tedious, so pay attention.
x >= -4 - Why is that?
Shouldn't that be x >= 4, TK? You need a 2nd coffee
Btw KentuckyCat, looking at this equation of yours:
sqrt(x+4) - sqrt(x-4) = 2
means the difference between the 2 squares is 8 :
x+4 is 8 greater than x-4, right?
so you can only have 9 and 1 (assuming integer solution):
sqrt(9) - sqrt(1) = 2 : 3 - 1 = 2 ; ok?
so x = 5 : capish
Shouldn't that be x >= 4, TK? You need a 2nd coffee
Btw KentuckyCat, looking at this equation of yours:
sqrt(x+4) - sqrt(x-4) = 2
means the difference between the 2 squares is 8 :
x+4 is 8 greater than x-4, right?
so you can only have 9 and 1 (assuming integer solution):
sqrt(9) - sqrt(1) = 2 : 3 - 1 = 2 ; ok?
so x = 5 : capish