(you should be able to solve yourself #4 and #6 from your post#16 now based on the last two post)
let me show you #1 from your post#16 which should allow you to fix #2 and #3 yourself

sqrt(9+4x)-1=sqrt(11+8x) first let's square both sides, ie

(9+4x)-2*sqrt(9+4x)+1=11+8x now consolidate so that the remaining square root is alone on one side

(9+4x)+1-(11+8x)=2*sqrt(9+4x) -> -2x-0.5=sqrt(9+4x) now we can square both sides again

4x^2+2x+0.25=9+4x -> 4x^2-2x-8.75=0 and from that you should get x=-1.25

actually since i do not have access to any tools i took an educated guess and assumed that the initial equation would resolve into likely either 1-1=0 or 2-1=1
and the second one works