PLEASE HELP Solve each equation:
a. x+3+3x=x+15
b. 3x+5=-3x+5x+10
c. n+n+3n=15

Marla bought a book for $12.95, a binder for $3.49, and a backpack for $44.99. the sales tax rate is 6%. find the amount of tax and the total she paid for these items

Arecipe calls for 2 2/4 cups of raisins, but julie only has a 1/4 measuring cup. how many 1/4 cups is needed to measure out 2 2/4 cups of raisins?

Which one is true about the hexagons ?