Final answer:
To find the value of r, we need to solve the given equation 2r + 5y = 18.
Step-by-step explanation:
To find the value of r, we need to solve the equation 2r + 5y = 18. Since this equation has two variables, r and y, we need more information to isolate r.
If you have another equation or value for y, please provide it so we can continue.