x + y = 14 -> (x+y)^2 = x^2 + 2xy + y^2 = 2xy + 100 = 14^2 = 196
2xy = 196 - 100 = 96
x^2 - 2xy - y^2 = (x - y)^2 = 100 - 96 = 4
x + y = 14
|x - y| = 2 -> x - y = +- 2
(x+y) + (x-y) = 2x = 14 +- 2 = {16, 12}, x = {8, 6}
(x+y) - (x-y) = 2y = 14 -+2 = {12,16}, y = {6,8}
Ответ: {x = 8, y = 6} U {x = 6, y = 8}
(5,4×(-1,7))×100/(5,1×0,6)×100=-(54×17)/(51×6)=
=-(9×1)/(3×1)=-3
7+8=15 45÷15=3 3×7=21 3×8= 24