Answer:
-9
Step-by-step explanation:
For a quadratic of the form

, we have the quadratic formula

,
where a is the coefficient (number before the variable) of the squared term, b is the coefficient of the linear term, and c is the constant term.
So, given

, we can get that

, and

. We substitute these numbers into the quadratic formula above.





This is our final answer.
If you've never seen the quadratic formula, you can derive it by completing the square for the general form of a quadratic. Note that the

symbol (read: plus or minus) represents the two possible distinct solutions, except for zero under the radical, which gives only one solution.
Answer:
-34
Step-by-step explanation:
Remove all brackets by multiplying the existing math signs then take it from there
The elapsed time is 2 hours and 45 minutes.You subtract the 8 from the 10, leaving 2 hours.You subtract the 10 from the 55, leaving 45 minutes.