Centuries: 1st century - 2nd century - 3rd century
Decades: 120s 130s 140s 150s 160s - 170s - 180s 190s 200s 210s 220s
Years: 169 170 171 172 173 - 174 - 175 176 177 178 179
Births
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... \pm \sqrt {b^2-4ac}}{2a} </math> The term b2 – 4ac is called the discriminant of the quadratic equation, because it discriminates between ...