Printer ink cartridges cost $19 each. The company that sells the ink cartridges charges a flat rate of $7.50, no matter how many ink cartridges you buy.

Write an algebraic expression that describes the total cost for a single order of `x`, cartridges.

The total cost for a single order of x cartridges can be represented by the following algebraic expression:

Total cost = (cost per cartridge * number of cartridges) + flat rate

In this case, the cost per cartridge is $19 and the flat rate is $7.50. Therefore, the algebraic expression is:

Total cost = (19 * x) + 7.50