Part A: first multiply 2 by x and -3, then combine the like terms, after that add 6 from both sides, then subtract 6x from both side, the answer is -5.
4x + 2(x-3) = 4x + 2x - 11
4x +2x -6 = 4x + 2x - 11
6x -6 = 6x - 11
6x = 6x -11 +6
6x = 6x -5
6x-6x= -5
0 = -5
part B) add the like terms
21 + 28 = 49 students
Ration of history 21 to students 49 = d)21:49

Step-by-step explanation:
find the value of the constant of proportionality k

c =total cost
d =days
Can you post the rest of the info? x
The top half is called the numerator.
The bottom is called the denominator.