Tell how many solutions each one has

Step-by-step explanation:

1) 3(x + 2 ) +4  = 31

3*x + 2*3 + 4 = 31

3x + 6 + 4 = 31

  3x + 10   = 31           {Subtract 10 from both sides}

          3x = 31 - 10

         3x = 21        {divide both sides by 3}

          x = 21/3

x = 7

This equation has one solution

2) 3x + 1 = 3x + 9

Subtract 3x form both sides

3x + 1 -3x = 3x + 9 - 3x

1 ≠ 9

There is no solution for this equation.

3) 2x - 4 = 2x -4

This equation has many solution

2

step-by-step explanation:

1+1=2