$$\frac{8\left(6x^{2}-2q\right)}{\left(3x^{2}-q\right)\times 56}$$
Cancel out $8$ in both numerator and denominator.$$\frac{6x^{2}-2q}{7\left(3x^{2}-q\right)}$$
Factor the expressions that are not already factored.$$\frac{2\left(3x^{2}-q\right)}{7\left(3x^{2}-q\right)}$$
Cancel out $3x^{2}-q$ in both numerator and denominator.$$\frac{2}{7}$$