6 be cause 8 times 6 equals 48
Factor the expression.
3(128j+3)
So you need to come up with a perfect square that works for the x coefficients.
like.. (2x + 2)^2
(2x+2)(2x+2) = 4x^2 + 8x + 4
Compare this to the equation given. Our perfect square has +4 instead of +23. The difference is: 23 - 4 = 19
I'm going to assume the given equation equals zero..
So, If we add subtract 19 from both sides of the equation we get the perfect square.
4x^2 + 8x + 23 - 19 = 0 - 19
4x^2 + 8x + 4 = - 19
complete the square and move 19 over..
(2x+2)^2 + 19 = 0
factor the 2 out becomes 2^2 = 4
ANSWER: 4(x+1)^2 + 19 = 0
for a short cut, the standard equation
ax^2 + bx + c = 0 becomes a(x - h)^2 + k = 0
Where "a, b, c" are the same and ..
h = -b/(2a)
k = c - b^2/(4a)
Vertex = (h, k)
this will be a minimum point when "a" is positive upward facing parabola and a maximum point when "a" is negative downward facing parabola.
As we already have the model that describes the change of the population in Italy in terms of the years that have elapsed, we only have to replace the conditions that are requested in that equation.
Therefore to find the population of Italy in the year 2000 (t = 10 years) substitute t = 10 in the equation and have:
million people
To find the population of Italy in 2008 (t = 18 years)
substitute t = 18 in the equation and have:
million people
To predict the population in Italy for 2015 and 2020 with this model, we substitute in the equation t = 25 and t = 30
t = 25
million people
t = 30
million people
B) is correct; on average, each bag of candy has a weight that is 2.6 oz different than the mean weight of 5 oz.
To find the mean absolute deviation, we first find the mean. Find the sum of the data points and divide by the number of data points (without the outlier, 21, in it):
(10+3+7+3+4+6+10+1+2+4)/10 = 50/10 = 5
Now we find the difference between each data point and the mean, take its absolute value, and find their sum:
|10-5|+|3-5|+|7-5|+|3-5|+|4-5|+|6-5|+|10-5|+|1-5|+|2-5|+|4-5| =
5+2+2+2+1+1+5+4+3+1 = 26
We now divide this by the number of data points:
26/10 = 2.6
This is a measure of how much each bag of candy varies from the mean.
