=(3x)/(3x+4)-(7)/(3x- 4)–(9x²+16)/((3х-4)(3х+4))=
=(3x*(3x-4)-7*(3х+4)-(9x^2+16))/((3x-4)(3x+4))=
=(9x^2-12x-21x-28-9x^2-16)/((3x-4)(3x+4))=
=-11*(3x+4)/((3x-4)(3x+4))=-11/(3x-4)=11/(4-3х)
О т в е т. 3)
((2x²y)/(15x⁴y³))·((35xy⁴)/(16x²))·((6)/(49y³))=
=(2x^2*y*35xy^4*6)/(15x^4y^3*16x^2*49y^3)=
=(x^3y^5)/(28x^6y^5)=1/(28x^3)
О т в е т. 1)