How can the commutative property be used to write multiplication sentences

Alocal concert promoter purchases 2 3/4 pages of ads. when one of the concerts is cancelled, the promoter cancels 1 5/8 pages of ads. how much advertising space is the concert promoter actually using?

In the figure below, segment ac is congruent to segment ab: triangle abc with a segment joining vertex a to point d on side bc. side ab is congruent to side ac which statement is used to prove that angle abd is congruent to angle acd? segment ad bisects angle cab. triangle acd is similar to triangle abd. segment ad is congruent to segment ac. angle cab is congruent to angle cba.

Which term best describes the association between variables a and b