The x coordinates of the points are -2, 1 and 3
To find standard deviation, take the average or mean of thegiven numbers.
[tex]\begin{gathered} \text{Let n be the total count of numbers} \\ Mean,x_i=\frac{\text{Sum of numbers}}{n} \\ =\frac{-2+1+3}{3}=\frac{2}{3} \end{gathered}[/tex]Now subtract the mean from eah number and take their squares.
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