After simplifying a student's work you find the statement 6 = 6. The student concludes the equation is an identity. Evaluate the correctness of that conclusion and explain the inference.

Solve: $7x-4=3x+12$

Solve for $x$: $\frac{2}{5}x-\frac{3}{4}=\frac{1}{10}x+\frac{7}{8}$

To solve the equation $0.05x-1.2=0.3$, which operation correctly clears the decimals while preserving the solution set?

A pharmacist combines $\frac{3}{8}x$ liters of Solution A with $\frac{1}{4}x$ liters of Solution B to create a $2$-liter mixture. By clearing the fractions first, determine the value of the scale factor $x$.