a+b=12
b+c=13
c+a=-15
\(\Rightarrow\)2(a+b+c)=12+13+(-15)
2(a+b+c)=10
a+b+c=10:2
a+b+c=5
\(\Rightarrow\)c=(a+b+c)-(a+b)=5-12=(-7)
a=a(+b+c)-(b+c)=5-13=(-8)
b=(a+b+c)-(c+a)=5-(-15)=20
\(\Rightarrow a=\left(-8\right)\)
b=20
c=(-7)
tim cac so a;b;c biet a+b=12;b+c= 13; c+a= -15. Cac so a;b;c lan luot la
a,Tim cac so nguyen a,b sao cho a.b=-3
b,tinh tong cac so nguyen x biet: -6<x+2<8
c,tim tat ca cac U(-15)
tim cac so tu nhien a,b,c nho nhat sao cho a/b=15/21 ;b/c=9/12 ;c/d=9/11
tim cac so nguyen a,b,c biet rang :a+b=11;b+c=3;c+a=2
1)tim cac so a, b,c biet rang :
a+b =3;b+c =5 va c+a =4
Tim tat ca cac so tu nhien a va b biet
a) a . b = 72 va ( a > 6 )
b) a . ( b - 3 ) = 15
c) ( a - 1 ) . ( b + 2 ) = 9
Tim cac so nguyen duong a,b,c biet rang:a^3-b^3-c^3=3ab va a^2=2(b+c)
b, tim n de [n+10].[n+21]=124689
c, tim cac chu so a,b biet aabb la so chinh phuong
tim cac so abc biet rang voi a,b,c khac nhau sao cho abc :(a+b+c)=25