Question

in a two-digit number, the tens digit is 5 less than the units digit. the number itself is five more than tree times the sum of its digits. what is the number?

Answer 1

Let t = the tens digit and u = the units digit.

t = u - 5

10t + u = 3(t + u) + 5

10t + u = 3t + 3u + 5

7t - 2u = 5

7(u - 5) - 2u = 5

7u - 35 - 2u = 5

5u = 40

u = 8, t = 3

The number is 38.