How was x = -7/4 worked out from the previous step? Show the steps.

The term $-3\frac{1}{2}$ can be written as:

$$-3\frac{1}{2} = -\left(3 + \frac{1}{2}\right) = -\left(\frac{3 \times 2}{2} + \frac{1}{2}\right) = -\left(\frac{6}{2} + \frac{1}{2}\right) = -\frac{7}{2}$$

The expression is:

$$x = \frac{-(-3\frac{1}{2})}{2(-1)}$$

Substitute $-\frac{7}{2}$ for $-3\frac{1}{2}$:

$$x = \frac{-\left(-\frac{7}{2}\right)}{2(-1)}$$

The numerator is $-\left(-\frac{7}{2}\right)$. A negative of a negative is a positive:

$$-\left(-\frac{7}{2}\right) = \frac{7}{2}$$

The denominator is $2(-1)$:

$$2(-1) = -2$$

Dividing by $-2$ is the same as multiplying by $-\frac{1}{2}$:

$$x = \frac{7}{2} \times \left(-\frac{1}{2}\right)$$ $$x = -\frac{7 \times 1}{2 \times 2}$$ $$x = -\frac{7}{4}$$

The final value is $-\frac{7}{4}$.