SOLUTION: Given Amod7=5 Bmod7=6 (A+B)mod7=Y Identify which one of the following options is a valid solution for Y ? -4 5 4 -7

Algebra ->  Complex Numbers Imaginary Numbers Solvers and Lesson -> SOLUTION: Given Amod7=5 Bmod7=6 (A+B)mod7=Y Identify which one of the following options is a valid solution for Y ? -4 5 4 -7       Log On


   

Question 1113998: Given
Amod7=5

Bmod7=6

(A+B)mod7=Y

Identify which one of the following options is a valid solution for Y ?



-4

5

4

-7

Answer by rothauserc(4718) About Me  (Show Source):
You can put this solution on YOUR website!
a = bmodn means that a = b +kn for some integer k
:
Amod7 + Bmod7 = 5 + 6 = 11
:
11mod7 = 4
:
note that 11 = 4 + 7, this is one solution
:
answer is 4
:
note that it can be proved that given Amod7=5 and Bmod7=6 then Amod7 + Bmod7 = (A+B)mod7 = (5+6)mod7
:
can you prove this using the definition of modulus above?
: