A roast beef sandwich costs $6.75. A customer buys multiple roast beef sandwiches. Write an equation that represents the situation. Use x to represent the number of roast beef sandwiches. Then determi

A roast beef sandwich costs $6.75. A customer buys multiple roast beef sandwiches. Write an equation that represents the situation. Use x to represent the number of roast beef sandwiches. Then determine how many sandwiches the customer buys.

 I know that the customer buys 5 roast beef sandwiches but I can't figure out the equation for the situation at hand