Answer:
81-25k²
Step-by-step explanation:
We need to write the expression for "The quantity 81 minus 5k, squared".
Square of any number x is given by x².
Square of 5k is given by : (5k)²= 5²×k²=25k²
Now subtract 25k² from 81.
It means we get : 81-25k². It is required expression.
Answer: The answer is 8.
Step-by-step explanation: The first step is to convert the expression into figures. We shall call the unknown number Y. So if we are told “the square of a number,” that means Y squared, or better still, Y^2. Further we are told “the difference between the square of a number and 40” and that can be written as;
Y^2 - 40.
Next we are told that this expression is equal to 3 times that number (that is 3Y). That can now be written out as follows,
Y^2 - 40 = 3Y
If we move all expressions to one side of the equation, what we would have is,
Y^2 - 3Y -40 = 0
(Remember that when a positive value crosses to the other side of an equation it becomes negative and vice versa)
We now have a quadratic equation
Y^2 -3Y - 40 = 0
By factorizing we now have
(Y -8) (Y + 5) = 0
Therefore Y - 8 = 0 or
Y + 5 = 0
Hence, Y = 8 or Y = -5
Since we are asked to calculate the positive solution, Y = 8
Answer: 16
Step-by-step explanation: 8+8 = 16
Step 1: Convert the denominators to the same number.
1/9 = 2/18
2/3 = 12/18
5/18
Step 2: Add the numerators.
12 + 2 + 5 = 19
Step 3: Convert to mixed number.
19/18 = 1 1/18
Hope this helps! :)
