What is the solution of the equation? i also need with this one .

15 = -x/5 ( it's a fraction)

a) -75

b) 3

c) -3

d) 75

True or false? many triangular shapes can be circumscribed about a given circle

Acircle has a radius of 5/6 units and is centered at (3.6, 7.8) write the equation of this circle

Two airplanes start at the same place and travel in opposite directions,one at 395 miles per hour and the other at 422 miles per hour. how many hours will it take for the planes to be 2451 miles apart?