NEED HELP someone help me

12x + 1 = 25 solve the following equation. then place the correct number in the box provided.

Successful implementation of a new system is based on three independent modules. module 1 works properly with probability 0.96. for modules 2 and 3, these probabilities equal 0.95 and 0.90. compute the probability that at least one of these three modules fails to work properly.

What is the missing reason in the proof? segment addition congruent segments theorem transitive property of equality subtraction property of equality?