What is the amount of sales tax on a suit priced at $2977 if the sales tax rate is 4%?

If tana tanb=k, show that(1+k)cos(a+b)=(1-k)cos(a-b)

Someone this asap for a group of students attends a basketball game. * the group buys x hot dogs at the concession stand for $2 each. * the group buys y drinks at the concession stand for $3 each. the group buys 29 items at the concession stand for a total of $70. how many hot dogs did the group buy?

Using elimination, what is -4x+2y=-12 4x+8y=-24