Respuestas

2012-11-30T07:11:21+01:00

2-3(r-7) = 4(r-2+8)

-1(r-7) = 4(r+6)

-1r+7 = 4r+24

-1r-4r = 24-7

-5r = 17

r = 17/5

r = 3.4