To find the number of visits per month at which the costs of the two plans are equal, we need to set up an equation based on the given cost structures.
For the first plan, the cost per visit is $20:
- Cost of first plan = \( 20x \) (where \( x \) is the number of visits)
For the second plan, the cost is a monthly fee of $45 plus $5 per visit:
- Cost of second plan = \( 45 + 5x \)
To find when the two costs are equal, we set the two equations equal to each other:
\[ 20x = 45 + 5x \]
So the correct equation is:
20x = 45 + 5x