Решить.

(4 х-3) (-2 х-8) = 0.

-8x²-32x+6x+24=0

-8x²-26x+24=0 | : 2

-4x²-13x+12=0 | · (- 1)

4x²+13x-12=0

D = b²-4ac = = 13² - 4·4· (-12) = 169 + 192 = 361

√D = √361 = 19

x1 = - b+√D = - 13+19 = 6 (сократим на 2) = 3

2a 2·4 8 4

x2 = - b-√D = - 13-19 = - 32 = - 4

2a 2·4 8

Ответ: x1 = 3; x2 = - 4.

4