Translate the following phrases into algebraic expressions:
a. The 4th term of an arithmetic sequence whose first term is 10 and whose difference is d
b. 19 less than twice a number
c. 19 times the square of a number
d. The difference between the square of a number and three times the number
a. An expression for the 4th term of an arithmetic sequence whose first term is 10 and whose difference is d is
(Type an expression using d as the variable. Simplify your answer)