Answer:
add 21 to both sides to get everything on one side
x^2 - 10x + 21 = 0
do factorization, guess and check
(x - 7) (x -3) = 0
x =7, and x =3
Answer:

Step-by-step explanation:
Lets solve the first half.

Second one:

Now compare.....Not the same right??
So your answer is: 
Hope this helps :)
There is not enough information to answer :(
Answer:
A. too much
Step-by-step explanation:
If we are only looking for how much water she drinks, we do not need to know the amount of hay or the amount of fruit