What is 2x + 3 = 15 ??

Does the problem involve permutations or? combinations? do not solve. the matching section of an exam has 4 questions and 7 possible answers. in how many different ways can a student answer the 4 ? questions, if none of the answer choices can be? repeated?

Iwant to know what 3g+5h+4g-2h is my teacher is too selfish to tell us

Match each inequality to the number line that represents its solution