Question

ai trả lời trước mà đúng thì tớ tick ch

tìm a,b,c,d thuộc z

a+b+c+d=1

a+c+d=2

a+b+d=3

a+b+c=4

Answer 1

Ta có: a+b+c+d=1

a+c+d=2

a+b+d=3

a+b+c=4

=>(a+b+c+d)-(a+c+d)=1-2 => b=-1

=>(a+b+c+d)-(a+b+d)=1-3 => c=-2

=>(a+b+c+d)-(a+b+c)=1-4 => d=-3

=> a = (a+b+c+d)-(b+c+d) = 1 - (-1-2-3) = 7

vậy a=7; b=-1; c=-2; d=-3

Answer 2

a+b+c+d=1

a+b+c=4

=>d=-3

a+b+d=3

=>c=-2

a+c+d=2

=>b=-1

a+b+c+d=1

=>a=7

Answer 3

vậy a = 7

b = 1 

c = 2

d = 3

Answer 4

a=7; b=1; c=1; d=3