Answer:
-5 sorry if it's wrong. I tried.
X= -3
Solution:
takeaway 4 from each side
x+3=0
subtract 3 from each side
x=-3
Answer:
B. 60.26°
Step-by-step explanation:
Given:
Consider the diagram representing the above scenario.
The top of the house where dad is standing is at A. The point where his son is standing is B. The bottom of the house is at C. AC is the height of house, BC is the distance between the house and son.
Height of the house (AC) = 21 ft
Distance between the house and son (BC) = 12 ft
Let the angle of depression for the dad be 'x'.
From the figure, it is clear that,
Angle of depression of the dad will be same as angle of elevation of Artie.
For triangle ABC,
Therefore, the angle of depression from the top of the house to the spot where Artie is standing is 60.26°.
Therefore, the correct option is option (B).
Answer:
iii. (l + m - n)(l - m + n)
vi. (5a -b) ( 5b - a)
Step-by-step explanation:
iii. l² - (m - n)²
= (l + m - n)(l - m + n)
vi. 4(a+b)² - 9(a-b)²
= (2(a+b))² - (3(a-b))²
= (2(a+b) + 3(a-b)) (2(a+b) - 3(a-b))
= (2a+2b + 3a - 3b) (2a+2b - 3a + 3b)
= (5a -b) ( 5b - a)
Answer:
Inference for Regression
Step-by-step explanation:
Let us try to understand the difference between each of them.
1) Two sample t- test : the following assumptions must be used while applying the t- tests.
- The samples of n observations X₁,X₂,X₃,...........X n is selected randomly.
- The population from which the small sample is drawn is normal.This is essential for X` and s , the two components of the statistics t, to be independent. it has , however been shown that slight departures from normality do not seriously effect the tests.
- <em>In case of two small samples both the samples are selected randomly , both the populations are normal and both the populations have equal variances.</em>
2) Chi - squared Test for independence:
The two attributes A and B are said to be independent if the actual frequency equals the expected one , that is, if (AB) = (A)(B)/ N
Similarly α and β will be independent is (αβ) = ( α)( β)/ N and so on.
3) Inference for Regression
When both X and Y are observed at random i.e the sample values are from a bi variate population there are two regression equations , each obtained by choosing that variable as dependent whose average value is to be estimated and treating the other variable as independent .
4) A N O V A
The various sources of variation , degrees of freedom , the sum of squares and the mean squares associated with the sources are generally shown in a table called analysis of variance table or A N O V A table.
5) Matched pairs
It can be used when the experiment has only two events or possibilities and each variable can be grouped in either of the two conditions. Example people having C O V I D 19 and not having C O V I D 19.