Question

Упростите выражение 3x(4x+7y)-(x+y)²

Answer 1

3x(4x+7y)-(x+y)²12x²+21xy-x²-2xy-y²11x²+19xy-y²=0D=361y²-44+y²=362y²-44362y²-44=0y²=0                 362y²-44=0y=0                   362y²=44                          y²=44/362                           y=22/181

Answer 2

12х+21ху-х-ху+у=11х+20ху+у