If x−y=80 and 3/5 = y/x , then what is the value of x?

(15 points and free brainiest )

If 10 men take 18 days to mow 60 acres of grass, how long will 15 men take to mow 80 acres?

Idont understand math at all! : o( use this scenario to answer the remaining questions: brenton purchased a new bedroom set for $4,500.00. he lives in arizona and pays a 8.75% sales tax. if he made a 50% down payment and financed the rest, what amount did he finance? what is the total sales tax brenton will pay? enter your answer in currency format, round to the nearest cent. what was brenton's total amount financed? enter your answer in currency format, round to the nearest cent.

Solve the triangle. a = 21°, c = 105°, c = 5