Question

Find the first term of a sequence x+1,2x-18,2x-1,if this sequence is an arithmetic progression​

Answer 1

Answer:

a₁ = 37

Step-by-step explanation:

In an arithmetic progression the common difference d is

d = a₂ - a₁ = a₃ - a₂ , that is

2x - 18 - (x + 1) = 2x - 1 - (2x - 18) ← distribute and simplify both sides

2x - 18 - x - 1 = 2x - 1 - 2x + 18

x - 19 = 17 ( add 19 to both sides )

x = 36

Thus

a₁ = x + 1 = 36 + 1 = 37