Answer:
either A or D
i would go with A
Step-by-step explanation:
Let's say each row sums to 15
If we had 3 rows, then the total sum would be 3*15 = 45
If we added all of the values in the 3x3 magic square, then we'd get 45 as well.
This is one example showing that
sum of all values = (number of rows)*(magic constant)
You can replace "rows" with columns to get the same idea, because each column also adds to the same magic constant. The diagonals are an exception since we only have two of them.
Answer:
The value of x is 23.
Step-by-step explanation:
Consider the below figure attached with this question.
Form the given figure it is clear that 
The sum of all exterior angles of a quadrilateral is 360°.
On combining like terms we get
Divide both sides by 15.
Therefore, the value of x is 23.
Answer:
<u>44 cows and 36 ducks.</u>
Step-by-step explanation:
x is ducks and y is cows.
Assuming both have 1 head each, we can write:
x + y = 80.
Let's assume each x(cow) has 4 legs and each y(duck) has two legs.
Then we can add the numbers of legs:
2x + 4y = 248 legs
Now rearrange x + y = 80 to:
x = 80-y
and substitute:
2x + 4y = 248 legs
2(80-y) + 4y = 248 legs
160 - 2y + 4y = 248 legs
2y = 88 legs
<u>y = 44 [There are 44 cows]</u>
Use this value to find the number of ducks:
x + y = 80
44 + y = 80
<u>y = 36 [There are 36 ducks]</u>
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Check:
Do 44 cows and 36 ducks have a total of 248 legs?
4*44 + 2*36 = 248 ?
176 + 72 = 248?
<u>YES</u>
The blank space is found by dividing 36a^2 by 12, which is equal to 3a^2
To get to this answer you need to
1. divide the both sides of the equation by 12.
2. subtract 2b^2 from both sides.
You will see that the blank space equals 3a<span>^2 then</span>
