First of all, i will start by representing the unknown value by x. The fish sandwich is represented by x. Anyway, you ordered 4 fish sandwiches which means 4 multiplied by x, which is 4x. The cost of the hamburger is $2.50 and the total bill, which is the fish sandwich plus the hamburger is $14.30. This can be represented mathematically by;
4x+2.50=14.30
Now, you have to subtract 2.50 from the both sides. That will be;
4x+2.50-2.50=14.30-2.50 (2.50-2.50 is 0 and 14.30-2.50 is 11.8)
Therefore;
4x=11.8
Divide the both sides by 4. That will be;
x=2.95. (4 divided by 4 1 and 11.8 divided by 4 is 2.95)
So the fish sandwich cost $2.95
Hope i helped.
