Simplify the following text for a Grade 4 native English-speaking person.
Original: The entry that lies in the i-th row and the j-th column of a matrix is typically referred to as the i , j , ( i , j ) , or ( i , j ) th entry of the matrix .
Simplified: The entry of a matrix A that lies in the row number i and column number j is called the i , j entry of A. This is written as A ( i , j ) or a ` ij .