Witch of the lines has a slope of 2?

Me! last question, and i'm stuck! write the algebraic expression that models the word phrase. the product of 2 divided by the number h and 8 more than the number k

If f(x)=3x+1 and f^-1=x-1/3, then f^-1(7)=

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