How do you find the values of x given #6xx21+7xx29-83=x#?
In calculations with different operations, always count the number of terms first. The plus and minus signs act as natural separators and prevent confusion as to which numbers belong together.
Each term simplifies to a single answer.
Within each term, the order to be followed is
Brackets, then powers and roots, then times and divide.
Keep the terms separate until the last line.