A large pizza at Lazarra's Pizzaeria cost $6.80 plus $0.90 for each topping. The cost of a large cheese pizza at Guido's Pizza is $7.30 plus $0.65 for each topping. How many toppings need to be added to a large cheese pizza from Lazarra's Pizzaeria and Guido's Pizza in order for the pizzas to cost the same, not including tax?