In the system –12c + 3d = 6 and –3c + 6d = –9, which expression could you use for substitution?
A. d = –1/2c – 3/2
B. c=-2d+3
C. c = 1/4d – 1/2
D. d = 4c – 2

Respuesta :

–12c + 3d = 6

12c = 3d - 6

c = 1/4 d - 1/2

Answer is

C. c = 1/4 d – 1/2