Answer:
Step-by-step explanation:
Key to this method is remembering that

So, if you divide the coefficient of x by 2 and square it, that will complete the square. With that in mind, things are easy.
6/2 = 3, so add 

So, c=9
Similarly, for the other two,

You don't really have to worry about the sign, since squaring will always make it positive

Answer:

Step-by-step explanation:
Let's try guessing...

All the units place has to be 4, if it is higher than 4 then the answer will not be 90 (the sum of the four rounded numbers).

This problem boils down to 5/6 - 1/4
To subtract these fractions you need a common denominator.
I'll use 12
The first fraction becomes 10/12 and the second fraction becomes 3/12
10/12-3/12 = 7/12
So Jacob is 7/12 of a foot taller than Linda.
Also note than since 12 inches = 1 foot, you could say Jacob is 7 inches taller than Linda
Answer:
68
Step-by-step explanation: