Answer:
rate of change: $0.35; initial value: $2.50; Equation: y= 0.35x + 2.50
Step-by-step explanation:
The rate of change is $0.35 because it's the one to change the total cost of the ice cream. If you get 3 toppings, you'll end up with 1.05 more dollars than if you had 0 toppings. And because of that, the initial value would also be $2.50, that's the minimum price you'll have to pay if you do want a sundae.
The equation is just restating all that, you start with the inital value b=$2.50, and the price will go up by 0.35 for every topping you add to the sundae.
Hope this helped :)
