Ответ:

  1. \(6(2x+15)-4(3x+8)=12x+90-12x-32=58\).
  2. \(3(5x+2y)-4(2x-3y)=15x+6y-8x+12y=7x+18y\).
  3. \(8(2x-y)-7(x-y)=16x-8y-7x+7y=9x-y\).
  4. \(6(5x-2y)-5(4x-3y)=30x-12y-20x+15y=10x+3y\).
  5. \(7(3x-5y)-4(2x+y)=21x-35y-8x-4y=13x-39y\).

Ответ: а) 58; б) \(7x+18y\); в) \(9x-y\); г) \(10x+3y\); д) \(13x-39y\).