For a new customer, a video store charges $10 for a rental card plus $2 per movie. write and solve a linear equation to find the cost for a new customer to rent 6 movies

Anything per something means that is a rate, so you will have a variable on that, such as x.

So $2 per movie, is interpreted as 2x

The $10 is a set price for a rental card, and will not change.

So a linear equation is interpreted as y = 2x + 10

Set x to 6 because you are renting that many movies. 

y = 2(6) + 10
y = $22

B12/23 is your answer