Răspuns :
a)(2x+3y)-(4x+y)-(10-4y)= 2x+3y-4x-y-10+4y=-2x+6y-10
b) (3x² -7xy)-(xy+5y²)-(x²-y²)= 3x²-7xy-xy-5y²-x²+y²=2x²-8xy-4y²
b) (3x² -7xy)-(xy+5y²)-(x²-y²)= 3x²-7xy-xy-5y²-x²+y²=2x²-8xy-4y²
A)2x+3y-4x-5y-10+4y= (am desfiintat parantezele dupa regula semnelor)
=-x+y-10
B)3x²-7xy-xy-5y²-x²+y²= (la fel am procedat;am desfiintat parantezele dupa regula semnelor)
=2x²-8xy-4y²=
=-x+y-10
B)3x²-7xy-xy-5y²-x²+y²= (la fel am procedat;am desfiintat parantezele dupa regula semnelor)
=2x²-8xy-4y²=