the sum of the digits of a 2- digit number is 9. if the tens digit is half of the ones digit , find the 2 digit number. pls help
a b
a + b = 9
a = (1/2) b
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(1/2) b + b = 9
so
(3/2) b = 9
so
b = 18/3 which is 6
which means a = 3
and a b is 36