Let k represent the cost of supplies, b the number of bottles, and c the number of cans. You know that the total cost is found by adding the number of bottles multiplied by the price of each to the number of cans multiplied by their unit price. (This is the computation performed anytime you purchase something.)

There are no constants in this equation.
-7 + 56x = 105
56x = 105 + 7
56x = 112
x = 2
If T is the midpoint of SU, then ST ≅ TU.
Therefore we have the equation:
6x = 2x + 32 <em>subtract 2x from both sides</em>
4x = 32 <em>divide both sides by 4</em>
x = 8
ST = 6x → ST = 6(8) = 48
TU = ST, therefore ST = 48
SU = ST + TU = 2ST, therefore SU = 2(48) = 96
<h3>Answer: ST = 48, TU = 48, SU = 96</h3>