What is the prime factorization of 80

How do i do this? i don’t understand

For the rule of 78, for a 12-month period, the last term in the sequence is 12 and the series sums to 78. for an 10 month period, the last term is and the series sum is . for a 15 month period, the last term is and the series sum is . for a 20 month period, the last term is and the series sum is

Which shows the graph of the solution set of 3y – 2x > –18?