Samuel's Flower Garden

In a garden, Samuel planted two types of flowers: roses and tulips. Let r represent the number of roses and t represent the number of tulips. Samuel planted a total of 150 flowers. The number of roses is 3 times the number of tulips. How many roses did Samuel plant?

To find the number of roses, we will set up the following equations:

$$r + t = 150$$

$$r = 3t$$