`a,6x(3x+5)-2x(9x-2)=17`
`<=>18x^2+30x-18x^2+4x=17`
`<=>34x=17`
`<=>x=1/2`
`b,2x(3x-1)-3x(2x+11)-70=0`
`<=>6x^2-2x-6x^2-33x-70=0`
`<=>-35x-70=0`
`<=>x=-2`
`c,(3x-1)(2x+7)-(x+1)(6x-5)=16`
`<=>6x^2+21x-2x-7-6x^2+5x-6x+5=16`
`<=>18x-2=16`
`<=>18x=18`
`<=>x=1`
`e,(4x+3)(4x-3)-(4x-5)^2=46`
`<=>16x^2-9-16x^2+40x-25=46`
`<=>-34+40x=46`
`<=>x=2`
`f,25x^2-9=0`
`<=>25x^2=9`
`<=>x^2=9/25`
`<=>x= +- ` $\sqrt[]{\frac{9}{5}}$
`<=>x=+-3/5`
