How do you solve this?

How do i do this activity, is appreciated

Mr. and mrs. wallace have decided to buy a car for $21,600. they finance $15,000 of it with a 5-year auto loan at 2.9% arp. what will be their monthly payment be? a. $268.20 b. $268.86 c. $269.54 d. $387.16 i need !

Which of the following quartic functions has x = –1 and x = –2 as its only two real zeroes?