Help?!?!

Find the value of x so that the three given terms are consecutive terms of an arithmetic sequence.

2x – 1, 4x, and 5x + 3

Guest Mar 5, 2017

#1**0 **

2x - 1 is the first term

And we have that the first term + d = the second term

2x - 1 + d = 4x → d = 2x + 1 (1)

And the first term + 2d = the third term

2x - 1 + 2d = 5x + 3 → 2d = 3x + 4 (2)

Sub (1) into (2) and we have that

2 [2x + 1] = 3x + 4

4x + 2 = 3x + 4 subtract 3x, 2 from both sides

x = 2 and using (1) → d = 2(2) + 1 = 5

So

The first term is 2(2) - 1 = 3

The second term is 4(2) = 8

And the third term is 5(2) + 3 = 13

Note that the difference between terms = d = 5

CPhill
Mar 5, 2017