Question

Determina x de modo que (x, 2x + 1,4x -2)seja uma p.a

Answer 1

$(x, 2x + 1,4x -2)$

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

$x+1=4x-2-2x-1$

$x+1=2x-3$

$x-2x=-3-1$

$-x=-4$

$x=4$

Answer 2

(x, 2x + 1,4x -2)
 
2x  + 1 - x  = 4x -2 - ( 2x + 1)
x + 1 = 4x -2 - 2x - 1
x - 2x = - 1 -3
 - x = - 4(-1)
   x = 4