1.
х² + 11х - 12 = 0,
Д = 11² - 4*1*(-12) = 121 + 48 = 169,
х1 = (-11 + 13) / 2*1 = 2/2 = 1,
х2 = (-11 - 13) / 2*2 = -24/2 = -12,
2.
х² - 20х = 0,
х * (х - 20) = 0,
х1 = 0, х - 20 = 0,
х2 = 20,
3.
-5х + 4(х - 6) ≥ 0,
-5х + 4х - 24 ≥ 0,
-х - 24 ≥ 0,
-х ≥ 24,
х ≤ -24
1.
х² + 11х - 12 = 0,
Д = 11² - 4*1*(-12) = 121 + 48 = 169,
х1 = (-11 + 13) / 2*1 = 2/2 = 1,
х2 = (-11 - 13) / 2*2 = -24/2 = -12,
2.
х² - 20х = 0,
х * (х - 20) = 0,
х1 = 0, х - 20 = 0,
х2 = 20,
3.
-5х + 4(х - 6) ≥ 0,
-5х + 4х - 24 ≥ 0,
-х - 24 ≥ 0,
-х ≥ 24,
х ≤ -24