What is 5x + 5 + 5x = -75

Can you simplify 4/7? 24 points will be awarded!

Stefanie is painting her bedroom. she can paint 2 1/3 square feet in 4/5 of an hour. how many square feet can she paint in one hour?

Me its important ! marge runs an ice cream parlor. her speciality is triple chocolate sundaes.she can prepare 1 sundae every 2 minutes, and she earns $1.20 for each sundae she makes . if she just makes sundaes for a single shift of at most 4 hours and at least 2 hours , which function relates her earnings to the number of minutes she works?