Решение:
-8x^2 + 6x + 5 = 0
Здесь a = -8, b = 6, c = 5.
D = 6^2 - 4 imes (-8) imes 5 = 36 + 160 = 196
x_1 = rac{-6 + √{196}}{2 imes (-8)} = rac{-6 + 14}{-16} = rac{8}{-16} = -0,5x_2 = rac{-6 - √{196}}{2 imes (-8)} = rac{-6 - 14}{-16} = rac{-20}{-16} = 1,25Ответ: -0,5; 1,25