1/3x - 2/3 = -18
1/3x = -18 + 2/3
x = -54 + 2
x = -52 answer
Let b=the number of boxes, c=cost of the pens
The expression that represents the total cost of the pens if a box costs 4 dollars and then she gets a 1 dollar discount for every additional box is c(b)=3b+1. We got this from the original equation c(b)=4+(4-1)(b-1). Simplify this and you will get c(b)=3b+1.
I believe that the type of triangle that is being represented is a equilateral triangle.
