Portuguese dominated the trade in the Indian Ocean which forms the first triangle and then they dominated trade from South America to Europe which is the other triangle
Step-by-step explanation:
Portuguese dominated the trade in the Indian Ocean as they were the ones making laws about the trade and were responsible for the naval presence tot the separate parts from the horn of Africa to the Indian and south east Asian coasts dominating the spice trade.
Apart from this they dominated trade from South America to Europe which is the other triangle and it was very lucrative as they had been able to colonize the region well and held on to Brazil for long.