SOLUTION: √(a-1)=a-3 what is the solution in simple terms please

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Question 1024879: √(a-1)=a-3 what is the solution in simple terms please
Answer by Edwin McCravy(20055) About Me  (Show Source):
You can put this solution on YOUR website!
sqrt%28a-1%29%22%22=%22%22a-3

Square both sides:

%28sqrt%28a-1%29%29%5E2%22%22=%22%22%28a-3%29%5E2

a-1%22%22=%22%22a%5E2-6a%2B9

0%22%22=%22%22a%5E2-7a%2B10

0%22%22=%22%22%28a-5%29%28a-2%29

%28a-5%29%28a-2%29%22%22=%22%220

a-5 = 0;   a-2 = 0
  a = 5;     a = 2

Test each in the original equation to test
for extraneous answers:

Test a = 5:

sqrt%28a-1%29%22%22=%22%22a-3
sqrt%285-1%29%22%22=%22%225-3
sqrt%284%29%22%22=%22%222
2%22%22=%22%222    

a = 5 is a solution.

Test a = 2:

sqrt%28a-1%29%22%22=%22%22a-3
sqrt%282-1%29%22%22=%22%222-3
sqrt%281%29%22%22=%22%22-1
1%22%22=%22%22-1    

a = 2 is not a solution.

Answer: a = 5

Edwin