5{x-2}-3{-x+1}
=5x-10+3x-3
=8x-13
{4a平方-3b平方｝-[2{a平方-1｝=2b平方-3]
4a^2-3b^2-2a^2+2-2b^2+3=0
2a^2-5b^2+5=0
4x-3y}-[{x-y}-{3x+y}]-5x
=4x-3y-x+y+3x+y-5x
=x-y