(5x-1) x - 10 ≤ 2 [4x² - (x+1)]
5x² - x - 10 ≤ 8x² -2x - 2
3x² - x +8 ≥ 0
a=3
b= -1
c= 8
Δ = b² - 4ac
Δ = 1 - 96 = -95
-b ± √Δ 1 ±√-95 1 ± i√95
x₁;₂ = --------------- = ------------ = -------------
2a 6 6
1 + i√95 1 - i√95
x₁ = --------------- x₂ = --------------
6 6