If this were to be graphed, the independent variable would be the price of the ticket for the rides. The dependent variable would be the total cost.
The fair admission is not a variable because it is a constant price for every single person who goes into the fair.
The problem asks to use y to represent the total cost and x to represent the number of ride tickets. In order to fully write out the equation, we have to figure out what the fair admission costs.
43.75 = 1.25(25) + b
*b represents the fair admission
Multiply 1.25 by 25
43.75 = 31.25 + b
Subtract 31.25 to find what b costs.
12.50 = b
The fair admission costs $12.50.
Solution: y = 1.25x + 12.50
Use the geometric mean for right triangles here. Like this

. Cross multiply to get

, and

. That simplifies down to

. Pull out the 9 as a perfect square of 3 and you're left with

, first choice above.
The fewest number of expressions is 3.
Answer:
John lost $6841.42.
Step-by-step explanation:
Let's find out how much John paid for the stock he bought. Each share cost $58.02. He bought 120 shares. Multiply the price by the number of shares.
58.02 x 120 = 6962.40
He sold the stock for $120.98 -- a huge loss! (We are not told that the $120.98 is the selling price of one share, so I'm assuming that's what John sold all his shares for.)
Find the difference to see what his loss was.
$6962.40 - $120.98 = $6841.42 LOST!