Solve for x

x/7+9=15

x=24
x=42
x=84
x=168

If cos(2x) = tan^2(y), show that cos(2y) = tan^2(x).

Atorch and a battery cost 2.50 altogether.the torch costs 1.50 more than the battery.what fraction of the total price is the torch? give your answer in its simplest form.

The moats separating people from the animals are 5 m wide for lions and 4 m wide for the elephants. if the lion’s moat is 4 m deep, how deep should the elephants’ moat be?