What is the constant of variation in the area formula #A = pir^2#? Precalculus Power Functions and Variation Modeling with Power Functions 1 Answer Konstantinos Michailidis Sep 13, 2015 It is #pi# Answer link Related questions What is meant by the phrase constant of proportion? What is the constant of variation in the circumference formula #C = 2pir#? What is a monomial function? The heat experienced by a hiker at a campfire is proportional to the amount of wood on the fire,... How do you solve #5^(x^2) = 25/(5^x)#? See all questions in Modeling with Power Functions Impact of this question 3517 views around the world You can reuse this answer Creative Commons License