Please help I don’t understand

This is so hard and it’s for a test

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?

If f(x) = x+8 and g(x) = 4x- 3, find (f+g)(x)