Question

Rezolva urmatoarele cerinte:
a) afla nr.a, daca ab +ac=520
si b+c=52;
b)afla nr.a, daca ab-ac=45
si b-c=9;
c) afla suma d+c daca
ab+ac+70=170 si a=25;
d) afla diferenta d-c, daca
ab-ac-48=2 si a=10.
Va rig frumos trebuie maine problena la mate neaparat
ca ne pune note dau si coronote si 20 de puncte!! Va rog plang

Answer 1

a)
ab+ac=520 => (prin factor comun) a(b+c)=520=> 52a=520=> a=520/52=> a=10

b)
ab-ac=45 => a(b-c)=45=> 9a=45=> a=45/9=> a=5

c) ab+ac+70=170
ab+ac=170-70
a(b+c)=100
25(b+c)=100
b+c=100/25 => b+c=4

d) ab-ac-48=2
a(b-c)=2+48
10(b-c)=50 => b-c=50/10=> b-c=5