Answer:
A
Step-by-step explanation:
Look at the y axis and find the highest point.
Answer:
Your work is correct as far as it goes. Now eliminate the terms that are zero.
Step-by-step explanation:
Multiplying anything by zero gives zero. Adding zero is like adding nothing. Zero is called the "additive identity element" because ...
a + 0 = a
Adding zero doesn't change anything. You can (and should) drop the zero if your goal is to simplify the expression.

Answer:
never
Step-by-step explanation:
if it still works then it is not worthless if its super old then it can be a collectors item
Answer:
-t2+10t-h+8 = 0
Step-by-step explanation: