Abigail is studying for the school spelling bee. She already knows 150 words from the vocabulary list. Each day, she learns 50 additional words from the vocabulary list.
Which equation can be used to determine the total number of words Abigail knows from the vocabulary list, y, over x days?
A. y = 50x + 150
B. y = 50(x + 150)
C. y = 50x - 150
D. y = 150x + 50
