Answer:
Both A and B are true identities
Step-by-step explanation:
A. N ( n − 2 ) ( n + 2 ) = n 3 − 4 n
We need to show that (left-hand-side)L.H.S = R.H.S (right-hand-side)
So,
n ( n − 2 ) ( n + 2 ) = n(n² - 2²) (difference of two squares)
= n³ - 2²n (expanding the brackets)
= n³ - 4n (simplifying)
So, L.H.S = R.H.S
B. ( x + 1 )² − 2x + y² = x² + y² + 1
We need to show that (left-hand-side)L.H.S = R.H.S (right-hand-side)
So,
( x + 1 )² − 2x + y² = x² + 2x + 1 - 2x + y² (expanding the brackets)
= x² + 2x - 2x + 1 + y² (collecting like terms)
= x² + 1 + y²
= x² + y² + 1 (re-arranging)
So, L.H.S = R.H.S
So, both A and B are true identities since we have been able to show that L.H.S = R.H.S in both situations.
In this situation, you have:
The mode is 79 (that’s the most common number).
The median is 78.5 (the middle value or the average of the two middle values, since there is an even number of test scores).
The mean is less than both of those, as it was brought down by the few scores of 49.
The means the mean will be less than median.
Answer: C
Remark
2015 is an odd numbered year. It is not a leap year. It has 365 days in it.
Equation
Total deaths = deaths / day * number of days
Givens
Total deaths = 32800
deaths / day = ???
number of days = 365
Sub and solve
32800 = x * 365 Divide by sides by 365
32800 / 365 = x
x = 89.86 deaths per day.
Problem
Do you round up, down or leave the number as it is?
I would round up 90 deaths per day.
Discussion
Just how much are you out?
Total deaths in a year (rounded) = 90 * 365
Total deaths in a year (rounded)= 32850 which is 50 too many
Suppose you round down
Total death/day = 89 * 365 = 39485 Rounding up is going to be better if you round at all.
Perhaps you should not round the answer at all and leave it at
89.86 <<<<< answer.
If you have choices, please list them.
Answer:
5
6
Step-by-step explanation:
To solve, collect like terms
x ≥ 2 + 21/2
x ≥ 4 1/2
the whole number that would be greater than 41/2 would be 5
2. 2.7 + 3.3 > x
6 > x
Step-by-step explanation:
Substitute the y in the 1st equation with the 2nd equation.
7x + 10(2x + 9) = 36
7x + 20x + 90 = 36
27x + 90 = 36
3x + 10 = 4
3x = -6
x = -2
So now we can find y.
y = 2x + 9 = 2(-2) + 9 = (-4) + 9 = 5.
So x = -2, y = 5.
