Answer:
u = 5 + t
Explanation:
t - u = -5
Your goal is to get the variable "u" alone, so your first step should be moving the "t" to the other side of the equation. You'll do this by subtracting "t" from both sides because "t-t" cancels each other out and the variable "t" ends up on the other side of the equation.
You should have this: -u = -5 - t
Next, you have to make "u" positive. You do this by dividing both sides of the equation by -1. This will make any negative number/variable positive and any positive number/variable negative.
And this is how you get your answer: u = 5 + t
Remember!
"t" is still a negative number!
Hope this helps! :)