Final answer:
The equation in slope-intercept form is y = 5x + 700, where x is the number of registered athletes and y is the total cost.
Therefore, the correct answer is: option A) y = 5x + 700
Step-by-step explanation:
The equation that represents Rory and Theresa's cost to run the sports camp, in slope-intercept form, takes into account a fixed cost and a variable cost per registered athlete.
The fixed cost for renting the facility is represented by the y-intercept (b), which is $700, as this is the cost when no athletes are registered (x = 0).
The variable cost is represented by the slope (m), which is $5 per registered athlete.
This leads us to the slope-intercept form of the equation: y = 5x + 700.
The correct choice is: A) y = 5x + 700