Solve the equation 3x = 2x + 18.

Step 1: Solve the equation $3x = 2x + 18$.
Sol:

$$3x = 2x + 18$$ $$3x - 2x = 18$$ $$x = 18$$

Check:
Take LHS:
Put $x = 18$

$$3(18)$$ $$= 54$$

Take RHS:
Put $x = 18$

$$2(18) + 18$$ $$= 36 + 18$$ $$= 54$$

Since LHS = RHS, the solution is correct.
Hence Checked.