Answer:
#4
[tex]6x+4x-5=24+9x\\ 6x+4x-9x=5+24\\ 19x=29\ \ |:19\\ x=\frac{29}{19}[/tex]
one solution
#5
[tex]25+4x=x+3x+7\\ 4x-x-3x=7-25\\ 0x=-18\\ 0=-18[/tex]
no solutions
#6
[tex]4x+8=4(x+2)\\ 4x+8=4x+8\\ 4x-4x=8-8\\ 0x=0\\ 0=0[/tex]
infinite number of solutions