+128407 x^2 - 7x - 6 = 0
Let a =1, b = -7 and c = -6
The "formula" is
[ - b ±√ [ b^2 - 4ac] ] / [2a]
Filling in the missing pieces, we have
[ - (-7) ±√ [ (-7)^2 - 4 (1)(-6) ] / [ 2(1) ]
[ 7 ±√ [ 49 + 24 ] ] / 2
[ 7 ±√ 73 ] / 2
So...the two solutions are
[ 7 +√ 73 ] / 2 and [ 7 -√ 73 ] / 2
