Evaluate f(x), evaluate f'(x) at x =4

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

Which of the following is best modeled using a linear equation y=ax+b, where a is less than 0?

Given: δabc, m∠1=m∠2, d∈ ac bd = dc m∠bdc = 100º find: m∠a m∠b, m∠c