Answer:
Step-by-step explanation:
f(x)=x is a line.
Start by combing like terms. You will get 3x+12=51. Now subtract 12 from both sides (3x=39). Divide both sides by 3 (x=13). The answer is 13.
About 100. (Im not quite sure)
5 2/3 = 17/3 = 34/6
8 5/6 = 53/6
34/6 - 53/6 = -19/6 = -3 1/6