SOLUTION: 2Square roor7x+4-1=7 find solutions of equation. check for extraneous solutions

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Question 75644: 2Square roor7x+4-1=7 find solutions of equation. check for extraneous solutions
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
sqrt%287x%29%2B4-1=7 Start with the given problem
sqrt%287x%29%2B3=7 Combine like terms
sqrt%287x%29=4 Subtract 3 from both sides
%28sqrt%287x%29%29%5E2=%284%29%5E2 Square both sides
7x=16
x=16%2F7 Divide both sides by 7. This is your answer


Check:
sqrt%287x%29%2B4-1=7
sqrt%287%2816%2F7%29%29%2B4-1=7 Plug in x=16%2F7
sqrt%28cross%287%29%2816%2Fcross%287%29%29%29%2B4-1=7
sqrt%2816%29%2B4-1=7
4%2B3=7
7=7 works