5-(t+3)=-1+2(t+3)

You need to get t on one side.

remove the ( )
5-t-3=-1+2t+6
UNDERSTAND that step, most beginning students err there.

Then, add t to both sides
5-3=-1+3t+6
subtract 5 from both sides.-3=3t
t=-1

now go back to the original, put for t -1, and see if it checks.

The book says it's 3..

Sure! Let's solve the equation step-by-step.

1. Start by simplifying both sides of the equation.
Distribute -1 and 2 to the terms inside the parentheses on the right side:
5 - t - 3 = -1 + 2t + 6

2. Combine like terms:
2 + t = 2t + 5

3. To solve for t, we need to isolate the variable on one side of the equation.
Start by moving the term with t to one side and the constant term to the other side.
Subtract t from both sides:
2 = 2t - t + 5

4. Simplify further:
2 = t + 5

5. To get t by itself, subtract 5 from both sides:
2 - 5 = t + 5 - 5
-3 = t

So, the solution to the equation is t = -3.

To check if it's correct, you can substitute -3 back into the original equation and see if both sides are equal.