2+2x{4+4x[5+5:(15-x)]}=58
2+2x{4+4x[5+5:15-5:x]}=
=2+2x{4+4x[5+1/3-5/x]}=
=2+2x(4+4x×5+4x×1/3-4x×5/x)=
=2+2x(4+20x+4x/3-20)=
=2+2x(20x+4x/3-16)=
=2+2x×20x+4x/3×2x-32x=
=2+40x×x+8x×x/3-32x=
= 6+120xx+8xx-96x/3=58
=> 6+120xx+8xx-96x= 174
=> 128xx-96x=168
x(128x-96)=168
x=168/128x-96
x=84/64x-48
x=42/32x-24
x=21/16x-12
x=21(16x+12)/16×16xx-144
