If dana school closes a phone she is used to contact each students family the secretary calls three families then each family cause three other families and so how many families will be notified during the six round of calls

So the first thing we do is to multiply the top equation by 3. the reason i want to do this is i notice there will be a 6y on both equations and can possibly add/subtract them. so we get 6y = -3x + 27. adding that and the second equation we get 6x = 27-15 which is 12. divide by 6 and we get 2. ∴ x = 2. substituting 2 into the first equation we get 2y = -2 + 9 which is 7. divide by 2 and we get 7/2. ∴ y = 7/2, x = 2.

61/100, because if it is 0.(value) than it is value / 100 assuming value is 2 digits long. we cannot simplify it further because 61 is prime number.