Solve "x^2 - 12x - 45 = 0" by completing the square
The equation is of the formx2+bx+c=0This means it can be rearranged to(x+(b/2))2=(b/2)2-cTaking the square root of both sides leaves us with x.
x2-12x-45=0(x-(12/2))2-(12/2)2-45 = 0(x-6)2-62-45 = 0(x-6)2 = 45 + 36(x-6)2 = 81x-6 = 9x= 6 + 9 = 15
EJ
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