How do I solve 39x-3y=21

What is the answer to 0.03:0.75

Vito uses 9 liters of water to water 24 flower pots. He is wondering how many liters of water it would take to water 40 flower pots. He assumes he'll use the same amount of water on each pot.

29) Find the area A and circumference Cof a circle of radius 7 mi. Express the answer in terms of pie

Mrs. Reed bought 48 items for her classroom. She bought some glue bottles. She bought 5 times as many pencils as she did bottles of glue.

Math Natalia Gonzalez You already owed your friend $6. This morning you borrowed $4 more and this afternoon you paid back $8. How much money do you owe your friend?

The profit of a business are RM 29,000. It is shared between two partners A & B. If A receives 9/20 of the profit, how much money does B receive?

One-third of the dairy cattle on a farm are in the barn. Three-fifths of the beef cattle are in the barn. There are 30 dairy cattle and 15 beef cattle in the barn. How many more dairy cattle are on the farm than beef cattle?

Which triangle always has three equal sides

21. Jackson played a video game for 1/6 hour. Hailey played a video game for 1/3 hour. Who played the video game for a greater amount of time? Explain.

Can someone explain what I think is "theta" and it looks like a 0 with a horizontal line through it?