What is the missing length?

Translate the word phrase into a math expression. 15 fewer than the product of 4 and a number. (pls immediately)

Find the exact value of each of the following. in each case, show your work and explain the steps you take to find the value. (a) sin 17π/6 (b) tan 13π/4 (c) sec 11π/3

Atriangle with all sides of equal length is a/an triangle. a. right b. scalene c. equilateral d. isosceles