+12 The equation of a parabola is given.
y=18x2+4x+20
What are the coordinates of the focus of the parabola?
Enter your answer in the boxes.
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+128408 y = 18x^2 - 4x + 20
y - 20 = 18 [ x^2 - 2/9 x +1/81 - 1/81 ]
y - 20 = 18 ( x - 1/9)^2 - 2/9
y - 180/9 + 2/9 = 18 (x - 1/9)^2
(y - 178/9) = 18(x - 1/9)^2
(1/18)(y - 178/9) = ( x - 1/9)^2
The vertex is (1/9, 178/9)
4a = 1/18
a = 1/72
The focus is ( 1/9, 178/9 + 1/72) = (1/9, 475/24)
