Jason’s bank account balance was $300. He paid of his bills. Now, his account balance is -$50.

Which equation can be used to find x, the total dollar amount of his bills?
a. -1/4x + 300 = -50
b. -1/4x - 300 = -50
c. 1/4x - 300 = -50
d. 1/4x + 300 = -50