Tell how many solutions each one has
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Answer:
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