Answer
TRUE
FALSE
TRUE
TRUE
Work Step by Step
a. 17 ≡ 2 (mod 5) <=> 5| 17-2
True since 5|15 => 15 = 5*{3} , 3 $\in$ Z
b. 4 ≡ −5 (mod 7) <=> 7 | -9
false since 9 and 7 are both prime so they don't divide each other
c. −2 ≡ −8 (mod 3) <=> 3| -8+2
True since 3|-6 since -6 = 3*{2), 2$\in$ Z
d. −6 ≡ 22 (mod 2) <=> 2|-6-22
True since 2|-28 since -28 = 2*{-14), -14$\in$ Z
