3(u-3)-7u=15 how do I find out what u is?

Vhich expression is equivalent to 6(3x + 4)? 9x + 418 x + 2418x + 49x + 10 i might ! i really do hope u see this and answer it

According to modern science, earth is about 4.5 billion years old and written human history extends back about 10,000 years. suppose the entire history of earth is represented with a 10-meter-long timeline, with the birth of earth on one end and today at the other end.

Two variables, x and y, vary inversely, and x=12 when y=4. what is the value of y when x=3?