Answer:
r = (-1)
Explanation:
Firstly simplify the brackets,
; -3(1 + 6r) = -3 - 18r
then substitute on the bracket with the simplified form,
; -3 - 18r = 14 - r
then move the values with (r) to one side and the other ones without (r) to the other side
; -3 - 14 = 18r - r
; -17 = 17r
then divide both sides by 17,
; -1 = r
Hence...r = -1