If the common difference in an arithmetic sequence is 4, and the 20th term is 36, what is the first term?
a. 40
b. 76
c. 40
d. 2 select the best answer from the choices provided a b c d

4 difference, subtract 20 point - 1st point, =19, 19 places x difference of 4= 76 more or less than 36. More would be 112, less would be -40. A and C are both 40 while choice B = the difference so I'd say it's supposed to be 1 of the 40's but it's missing the negative sign