Step-by-step explanation:
f(x)=x²+10x-24
please rate and mark as brainliest
Answer:
24 terms
Step-by-step explanation:
The sum of an arithmetic sequence is the average of the first and last terms, multiplied by the number of terms. The last term is given by ...
an = a1 + (n-1)d
We have a sequence with first term a1 = 2 and common difference d = 2. So the last term is ...
an = 2+ 2(n -1) = 2n
Then the average of first and last terms times the number of terms is ...
Sn = 600 = n(2 + 2n)/2 = n(n+1) . . . . . . close to n²
We can solve the quadratic in n, or we can estimate the value of n as the integer just below the square root of 600.
√600 ≈ 24.5
so we believe n = 24.
_____
<em>Check</em>
S24 = 24·25 = 600 . . . . . . as required.
Answer:
(C) Whether or not a subject attends preschool
Step-by-step explanation:
In research studies, variables are used to explain differences in another variable. The explanatory variable (also known as independent or predictor variable) is used to explain differences in the response variable (dependent or outcome variable).
<em>It is important to know that the explanatory variable is the variable that is manipulated by the researcher. </em>
The facts that are not being manipulated are the income of the children studied, and what happens after attending or not preschool program. The variable the researcher is manipulating is the assignation to groups that will or will not attend preschool. Therefore the correct answer is:
(C) Whether or not a subject attends preschool
I hope you find this information useful and interesting! Good luck!
This is something you'll need a T table for, or a calculator that can compute critical T values. Either way, we have n = 10 as our sample size, so df = n-1 = 10-1 = 9 is the degrees of freedom.
If you use a table, look at the row that starts with df = 9. Then look at the column that is labeled "95% confidence"
I show an example below of what I mean.
In that diagram, the row and column mentioned intersect at 2.262 (which is approximate). This value then rounds to 2.26
<h3>
Answer: 2.26</h3>
X - 9 + 2wx = y Add 9 to both sides
x + 2wx = y + 9 Factor out the x
x (1 + 2w) = y + 9 Divide both sides by (1 + 2w)
x = (y + 9) / (1 + 2w)