One minute later at 8:01pm. One lighthouse will flash 3 times (at 20, 40 and 60 seconds)...the other will flash twice (at 30 and 60 seconds). So they will both flash 60 seconds later, at 8:01
        
             
        
        
        
Answer:
B
Step-by-step explanation:
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X + 5 + 11x = 12x + y
Simplify: 12x + 5 = 12x + y (We are adding x and 11x on the left side)
Subtract 12x from each side makes each zero.
5 = y
So we can plug in and test. I'm picking two random numbers to plug in for x. 10, and 82
x = 10, y = 5
10 + 5 + 11(10) = 12(10) + 5
125 = 125
x = 82, y = 5
82 + 5 + 11(82) = 12(82) + 5
989 = 989
So we verified y = 5