6. Решить уравнения: a) 3(3x-1)+2=5(1-2x)-1 6) + = 10 в) -3x²-1.5x = 0

Решение:

a) \[3(3x - 1) + 2 = 5(1 - 2x) - 1\]

\[9x - 3 + 2 = 5 - 10x - 1\]

\[9x - 1 = 4 - 10x\]

\[9x + 10x = 4 + 1\]

\[19x = 5\]

\[x = \frac{5}{19}\]

б) \[\frac{x}{7} + \frac{2x}{21} = 10\]

\[\frac{3x}{21} + \frac{2x}{21} = 10\]

\[\frac{5x}{21} = 10\]

\[5x = 210\]

\[x = \frac{210}{5}\]

\[x = 42\]

в) \[-3x^2 - 1.5x = 0\]

\[-1.5x(2x + 1) = 0\]

\[-1.5x = 0 \quad \text{или} \quad 2x + 1 = 0\]

\[x = 0 \quad \text{или} \quad 2x = -1\]

\[x = 0 \quad \text{или} \quad x = -\frac{1}{2} = -0.5\]