Question

Calcul algebric. Operații cu numere reale reprezentate prin litere. Adunarea și scăderea.

Efectuați:

a) 11m+(3n-5m+6)-(4m-2n-8)=

b) (3x+10y)-(5x+4y)-(7x-2y)=

c) 2,6xy-2,(3)xy+1,(6)xy+(2,3xy-0,9xy)=

Answer 1

a) 11m+(3n-5m+6)-(4m-2n-8)=11m+3n-5m+6-4m+2n+8=
=2m+5n+14
b) (3x+10y)-(5x-4y)-(7x-2y)=
= 3x+10y-5x+4y-7x+2y=
=16y-8x=8(2y-x)
c) 2,6xy-2,(3)xy+1,(6)xy+(2,3xy-0,9xy)=
=26:10xy-21:9xy+15:9xy+14:10xy=
=13:5xy-7:3xy+7:5xy=
=xy(13:5-7:3+7:5)= 
=xy(20:5-7:3)=
=xy(4-7:3)= aici aduci la acelasi numitor
=xy(12:3-7:3)=
=5:3xy