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?
The second condition tells you that \(t\) is half the size of \(u\), so \(t=\dfrac12u\), which could be rewritten in several ways. In standard form, that would be \(2t-u=0\).
Answer:t=\(\frac{u}{2}\)
Step-by-step explanation:
First equation t+u=9
Second equation t = \(\frac{u}{2}\) 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