<PRE><B>Question 195418</B>
7x^2-2x-9=0
7x^2-2x = 9
7(x^2 -(2/7)x ) = 9
7(x^2 -(2/7)x + __ ) = 9
7(x^2 -(2/7)x + 1/49 ) = 9 + 7(1/49)
7(x^2 -(2/7)x + 1/49 ) = 441/49 + 7/49
7(x - 1/7)^2 = 448/49
(x - 1/7)^2 = 64/49
x - 1/7 = 8/7
x = 9/7
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