Step 1: Interpret the notation.
The term "finite 7" in this context typically refers to operations within the ring of integers modulo 7, denoted as Z7. This means all calculations are performed, and results are expressed, as remainders when divided by 7. The equation x−4=4(finite7) is interpreted as a congruence:
x−4≡4(mod7)
Step 2: Solve the congruence for x.
To isolate x, add 4 to both sides of the congruence:
x−4+4≡4+4(mod7)
x≡8(mod7)
Step 3: Simplify the result modulo 7.
To simplify 8(mod7), we find the remainder when 8 is divided by 7.
8=1×7+1
The remainder is 1. Therefore, 8≡1(mod7).
Substituting this back into the congruence for x:
x≡1(mod7)
This means x is any integer that leaves a remainder of 1 when divided by 7. For example, x could be 1,8,15,−6, and so on. If a single value from the set {0,1,2,3,4,5,6} is expected, then x=1.
The simplified form of the equation is:
x≡1(mod7)