Help it’s for algebra 1

Find the value of x for which abcd must be a parallelogram -9-6x x-30

Ithink i know it but i want to be sure so can you me out ?

In stepmber, daniel and justin opened a business. during their first three months of business, their average monthly profit was $51. if during their first month, they lost $29, and during their second month, they gained $115, what was their profit or loss for their third plzzz i will give you 299 points