SOLUTION: pls help me to answer. if x^2-3x+1=0, find the value of x^2+1

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Question 923984: pls help me to answer. if x^2-3x+1=0, find the value of x^2+1
Answer by josgarithmetic(39618) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2-3x%2B%283%2F2%29%5E2-%283%2F2%29%5E2%2B1=0, for completing the square;
%28x-3%2F2%29%5E2=%283%2F2%29%5E2-1
%28x-3%2F2%29%5E2=9%2F4-4%2F4
%28x-3%2F2%29%5E2=5%2F4
x-3%2F2=0%2B-+%281%2F2%29sqrt%285%29
x=3%2F2%2B-+%281%2F2%29sqrt%285%29

Look again at the original quadratic equation.
x%5E2%2B1=3x, and you already see the solution obtained for x.

highlight%28x%5E2%2B1=9%2F2%2B-+%283%2F2%29sqrt%285%29%29