(xy - 2x + 5y) × 3 + 2(2xy + 3x - 6y),если x=1. 2/7 y=-5/6

Question

(xy - 2x + 5y) × 3 + 2(2xy + 3x - 6y),если x=1. 2/7 y=-5/6

Answer 1

(xy- 2x + 5y) × 3 + 2(2xy + 3x - 6y),если x=1. 2/7 y=-5/6
3xy-6x+5y+4xy+6x-12y=7xy-7y=7y*(x-1)=7*(-5/6)*(1(2/7)-1)=(-(35/6))*((9/7)-1)=(-35/6)*((9-7)/7)=(-35/6)*(2/7)=(-35*2)/(6*7)=-70/42=-10/6=-5/3=-1(2/3);