Respuesta :

Answer:

(15+3d)/6 = c

2 1/2 + 1/2d = c     (more simplified)

Step-by-step explanation:

15 = -3(2c +d)

15 = -6c -3d

+3d       +3d

15 +3d = -6c

/-6          /-6

(15+3d)/6 = c

2 1/2 + 1/2d = c