I picked (-x, y) and it said it was incorrect I really do not understand this at all someone please help

Ifurniture stores having a weekend sale and is offering 20% discount on patio chairs and table the sales tax on furniture is 6.25 using function composition how can you represent the total amount a that you would need to pay for this furniture that cost x dollars

Can you me find the missing length. i attached an image.

Determine which postulate or theorem can be used to prove that lmn =nmo