1,
`4x(x-5)-(x-1)(4x-3)=5`
`<=>4x^2-20x-(4x^2-3x-4x+3)=5`
`<=>4x^2-20x-4x^2+3x+4x-3-5=0`
`<=>-13x-8=0`
`<=>-13x=8`
`<=>x=-8/13`
2,
`(3x-4)(x-2)=3x(x-9)-3`
`<=>3x^2-6x-4x+8=3x^2-27x-3`
`<=>3x^2-10x-3x^2+27x=-3-8`
`<=>17x=-11`
`<=>x=-11/7`
3,
`(x-5)(x-4)-(x+1)(x-2)=7`
`<=>x^2-9x+20-(x^2-x-2)=7`
`<=>x^2-9x+20-x^2+x+2=7`
`<=>-8x=-15`
`<=>x=15/8`