If you would like to solve for the positive value of x, you can do this using the following steps:
6 * x^2 - 54 = 0 /6
x^2 - 9 = 0
(x - 3) * (x + 3) = 0
1. x = 3
2. x = - 3
The correct result would be x = 3.
<h3>
Answer: 28</h3>
==========================================================
Explanation:
Method 1
Imagine a table with 8 rows and 8 columns to represent all possible match-ups. You can actually draw out this table or just think of it as a thought experiment.
There are 8*8 = 64 entries in the table. Along the northwest diagonal, we have each team pair up with itself. This is of course silly and impossible. We cross off this entire diagonal so we drop to 64-8 = 56 entries.
Then notice that the lower left corner is a mirror copy of the upper right corner. A match-up like AB is the same as BA. So we must divide by 2 to get 56/2 = 28 different matches.
----------------------------------
Method 2
There are 8 selections for the first slot, and 8-1 = 7 selections for the second slot. We have 8*7 = 56 permutations and 56/2 = 28 combinations.
----------------------------------
Method 3
Use the nCr combination formula with n = 8 and r = 2
There are 28 combinations possible. Order doesn't matter (eg: match-up AB is the same as match-up BA).
Notice how the (8*7)/2 expression is part of the steps shown above in the nCr formula.
Answer:
-4
Step-by-step explanation:
Low tide is 1 ft below average water level.
High tide is 5 ft higher than low tide.
High tide is 5 ft higher than low tide. Start at low tide. Use 1 ft of the 5 ft to go up to average water level. You still have 4 ft more to go to high tide. That means high tide is 4 ft above average water level. Then, the average water level is 4 ft below high tide. A height below another height is is a negative number of feet from that height. Since the average water height is 4 ft BELOW high tide, then relative to high tide, the average water level is -4 ft.
Answer: -4
First, do what's in the paranthesis:
(4*4-12)
Multiplication first:
16-12
Then subtract:
4
We get:
5-1+2*4*8
Multiply:
2*4
8
Multiply, again:
8*8
64
We get:
5-1+64
Subtract:
5-1
4
Add:
4+64
Answer: 68
Answer:
There are many examples the basics are also easy to remember.
Step-by-step explanation:
We can input these for the following equation.
x > 5
(x is greater than 5)
Then compare to - x < 5
(minus x is less than 5)
We try a sum
3x -2 ≤ 1
we can then balance subtract -2
3x ≤ -1
then divide by 3
x= -1 /3
We try another value
3x -2 ≤ 0
1 ≤ 3x
1/3 ≥ x
We can check that each equality fits and alter the number accordingly.
For the first one we are saying it is no greater than 1
For the second we say it is greater than zero.
We are able to prove both have the answer.
Just like when we look for negative percentages and count down we record this as we count in mental math.
