<PRE><B>Question 609287</B>
103 = 9a + 3b + c
163 = 49a + 7b + c
328 = 144a + 12b + c

Solve for c:
103 = 9a + 3b + c
c = 103 - 9a - 3b

Plug c into other equations:
163 = 49a + 7b + 103 - 9a - 3b
Combine like terms:
60 = 40a + 4b
328 = 144a + 12b + 103 - 9a - 3b
225 = 135a + 9b

Work with these two equations:
60 = 40a + 4b
225 = 135a + 9b

Solve for b: 
60 = 40a + 4b
*2     *2
120 = 80a + 8b

225 = 135a + 9b
- 120 = - 80a - 8b
105 = 55a + b
b = 105 - 55a

Substitute b into one of equations:
60 = 40a + 4b
60 = 40a + 4(105 - 55a)
60 = 40a + 420 - 220a
-360 = -180a
a = 2

Substitue a into equation:
60 = 40a + 4b
60 = 40(2) + 4b
60 = 80 + 4b
-20 = 4b
b = -5

Substitute a and b into one of the first equations:
103 = 9a + 3b + c
103 = 9(2) + 3(-5) + c
103 = 18 - 15 + c
103 = 3 + c
c = 100

Check with other 2 equations.
So the quadratic function is 
{{{ Camera(x) = 2x^2 - 5x + 100 }}}
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