I think it’s is c I’m not sure tho
For this case we have:
Cost of manufactures of T-shirts 
where x represents the number of T-shirts
Part A:
Substituting
in the total cost equation you have to:

Thus, the cost of 8 shirts will be 
Part B:
If
then

Thus, the cost of 12 shirts will be 
Answer:

If the perimeter is 98 cm, the sum of the lengths of two adjacent sides is 49 cm.
... (2x -1) + (3x +5) = 49 . . . . use the given information and relation
... 5x +4 = 49 . . . . . . . . . . . simplify
... 5x = 45 . . . . . . . . . . . . . . . subtract 4
... x = 9 . . . . . . . . . . . . . . . . . divide by 5
The left side dimension is then
... 2x -1 = 2·9 -1 = 17 . . . . cm
The top dimension is
... 3x +5 = 3·9 +5 = 32 . . . . cm
The rectangle is 17 cm by 32 cm.
The correct expression is A.
Not sure if there're any answer choices of some sort,
but if the angle a and angle b are supplementary, that means when you add their measures together they must equal 180.