Which topic is the most likely to be the finale and find the law in the final exam of the seventh grade mathematics?

The deformation of several multiplication formulas in mathematics is bound to be tested.

Example: Given that m-2n = 3 and Mn = 2, find the square of (1)(m+2n)(2)m-the square of Mn+4n.

Because m-2n = 3 and Mn = 2, the square of (m-2n) = the square of m-the square of -4mn+4n = the square of m-the square of 8+4n =9.

So the square of m+the square of 4n = 17.

Square of (1) (m+2n) = square of m+square of +4mn+4n =25.

(2) the square of m-the square of Mn+4n = 15.