Answer:
2nd equation: 5x + 14 - 4x = 23 + x - 9
Explanation:
12+4x=6x+10-2x
12+4x=4x+10
12=10
No solutions
5x+14-4x=23+x-9
x+14=14+x
x=x
Infinitely many solutions
x+9-0.8x=5.2x+17-8
0.2x+9=5.2x+9
0.2x=5.2x
0=5x
0=x
One solution
4x-2x=20
2x=20
x=10
One solution