Question

The sum of the two digits of a number is 9. If the tens digit is one-half the units digit, what is the number? Let t = the tens digit, u = the units digit, and t + u = 9. Which of the following equations would complete the system?

Answer 1

The second condition tells you that
`t` is half the size of
`u`, so
`t=\frac12u`, which could be rewritten in several ways. In standard form, that would be
`2t-u=0`.

Answer 2

Answer:t=
`(u)/(2)`

Explanation:

First equation t+u=9

Second equation t =
`(u)/(2)` since the number in the tens position is one half of the one in the units. So if you divide u by two, you should have one t, as the equation states