math precalculus

Question

Determine the first term for the arithmetic sequence given the following values: t₃₃ = 92, d​​​​​​​ = -2

Answer 1

33rd term = 92, common difference =-2

32 terms difference from a1 to a33 (or from t1 to t33)

32 x -2 = -64

92+64 = 156 = t1 (or a1) it's an arithmetic sequence

a1 = 156

a2 = 154

a3 = 152

a4 = 150

(150-100 = 50

... 29-4 =25

50/25 = 2

....

a29=100

a30 = 98

a31= 96.

a32 = 94

a33= 92