Quadratic equation: yes or no?
x² - 3x + 9
Yes, it is a quadratic equation.
(x - 9)² = 121
x = -2 or x = 20
48x² + 56x + 16 (use diamond method)
x = -½ or x = -⅔
x² - 8x - 42 = 0
x = 4 + √58 or
x = 4 - √58
x² - 8x + 12
x = 6 or x = 2
x - 2 = 7
No, it is not a quadratic equation
(8x - 1)(8x + 1)
x = ⅛ or x = -⅛
x² - 17x = -30
x = 15 or x = 2
x² + 6x - 16 = 0
x = 2 or x = -8
(6x + 3)(x - 2)
x = 2 or x = -1/2