Blackhorse productions, inc., used the aging of accounts receivable method to estimate that its allowance for doubtful accounts should be $20,150. the account had an unadjusted credit balance of $10,200 at that time. the appropriate bad debt adjustment was recorded. later, an account receivable for $1,200 was determined to be uncollectible and was written off. required: for each transaction listed above, indicate the amount and direction (+ for increase or − for decrease) of effects on the financial statement accounts and on the overall accounting equation. (enter any decreases to assets, liabilities, or stockholders equity with a minus sign.)