Y= (15-2x)^2(x+3) can you guys me with this one? all i know is the i can use the zero product property on the x-intercepts

and y = x(2x+5)(2x-7)

actually

Offering 30 if a plus b plus c equals 68 and ab plus bc plus ca equals 1121, where a, b, and c are all prime numbers, find the value of abc. the answer is 1978 but i need an explanation on how to get that.

Atourist boat is used for sightseeing in a nearby river. the boat travels 2.4 miles downstream and in the same amount of time, it travels 1.8 miles upstream. if the boat travels at an average speed of 21 miles per hour in the still water, find the current of the river.

Quickly, you! v v v v v v v v v v v v