Iam very confused on what they are asking may you me

Which value of c would make he following expression completely factored? 8x+cy

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.

How to use order of operation in 20 divide by 4 multiply 5 = 1