The first 3 term of an AP are x,2x+1 and 5x-1 find x and the sum of the first 10 terms

Answer 1

d = 2x+1-x=x+1
S10 = 10/2 (2*x+9(x+1))
= 5(11x+9)
= 55x+45

(2x+1)-x = (5x-1)-(2x+1)
Now find x

Answer 2

How to solve this math