Prove that cos(x+y) +cos(x-y) =2cos x cos y

Which expression is equivalent to 5r6141 2r+st6

How to choose the sign of the radical in the denominator of the formula for the distance from a point to a line.

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 (monthly car loan payment per $1,000 borrowed) i need !