What's the value of (-7)(-6)

Fast phone couldn’t copy and paste so i decided to right it down

Which of these people has balanced their checkbook correctly? oa. gary: the balance in his check register is $500 and the balance in his bank statement is $500. b. gail: the balance in her check register is $400 and the balance in her bank statement is $500. c. gavin: the balance in his check register is $500 and the balance in his bank statement is $510.

Δabc is reflected across line l to form δ alblcl, and a¯¯¯al¯¯¯¯ intersects line l at point d. which equation is not necessarily true?