Oblicz wartość liczbową wyrażenia, dla x= -2 y=3 -(-3xy+2x-5y)+(-2+4y-8xy)-(5xy-5x+4y)= (3x²-4y)+(2x²+6y)-(5x²-7y)+(-2x²4y)= (5+x-y)-(3-y+x)+(6-x+2y)-(-5+2x-4y)=

x=-2 y=3 a)-(-3xy+2x-5y)+(-2+4y-8xy)-(5xy-5x+4y)= =-(-3*-2*3+2*-2-5*3)+(-2+4*3-8*-2*3)-(5*-2*3-5*-2+4*3)= =-(18+(-4)-15)+(-2+12-(-48))-(-30-(-10)+12)= =-(-1)+58-(-8)=59-(-8)=67 b) (3x^2-4y)+(2x^2+6y)-(5x^2-7y)+(-2x^2 4y)= =(3*-2^2-4*3)+(2*-2^2+6*3)-(5*-2^2-7*3)+(-2*-2^2*4*3)= =(12-12)+(8+18)-(20-21)+(-96)= =0+26-(-1)+(-96)=27+(-96)=-69 c) (5+x-y)-(3-y+x)+(6-x+2y)-(-5+2x-4y)= =(5+(-2)-3)-(3-3+(-2))+(6-(-2)+2*3)-(-5+2*-2-4*3)= =(3-3)-(0+(-2))+(8+6)-(-5+-4-12)= =0-(-2)+14-(-9-12)= =2+14-(-21)= =16-(-21)=16+21=37