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Find and solve a matrix equation?

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y=a+bx+cx2  write this using each point as
4=  a+b+c      for (1,4)
8=  a+2b+4c  for (2,8)
14=a+3b+9c for (3,14)
 
The matrix equation is a 3×3 matrix,  a column of unknowns = a column vector of y's
 
1   1   1 | a       4
1   2   4 | b   =  8
1   3   9 | c       14
 
The inverse matrix is
3      -3     1
-2.5   4    -1.5
.5      -1     .5
 
The unknown coefficients are
3      -3     1      |  4                2
-2.5   4    -1.5   |  8             = 1
.5      -1     .5    |  14               1
 
The curve is y = 2 + x + x2
I have clearly not described the computation of the inverse matrix.  I was lazy and did it using MINVERSE in EXCEL