When creating the following sentence, after the leftmost form - A = B * ( + ) or the rightmost form - = * ( + C ). Why would be equal to A, instead of B or C?

Also when selecting statements, are you able to select which statement at random, or should it follow and PEMDAS? For example, do I have the option of creating the statement as - A = B + ( A + C )

ABC + | * 1 ( ) A derivation is a repeated application of rules, starting with the start symbol and ending with a sentence (all terminal symbols) I sid> Leftmost Rightmost => = => A = => A= * => A = B => A = B * ( ) => A = B (Kid>+ ) => A = B * ( A + ) => A = B * ( A + ) => A = B * (A + C) => : => = * => = * ( ) => = * ( + = * ( + ) => = * ( +C) => = * (A+C) => =B* (A + C) => A=B* (A +C)