Question

3. If x +4, 2x+5, and 4x +3 represent the first three terms of an arithmetic sequence, then find the

Answer 1

first term = initial number

second term = initial number + common difference

third term = initial number + 2(common difference)

So...

2x+5-(x+4) = common difference

4x+3-(2x+5) = also common difference

2x+5-(x+4) = x+1

4x+3-(2x+5) = 2x-2

Because x+1=2x-2 we can solve for x.

x=3

So the sequence goes... 7,11,15...

19 is the fourth term