Answer:
Reflexive Property
ASA
CPCTC
Step-by-step explanation:
The true statement is as follows "No because she did not use a simple random sample".
<h3>What is random sampling?</h3>
Random sampling is the method to choose the given samples of observation to make assumptions about the population.
It is given that
Population: All tenth-grade girls
Sample: 20 intramural tennis players
The 20 intramural tennis players cannot represent all tenth-grade girls.
This is so because the selection is biased here, and it could not be used to make inferences about the overall population. then she did not use a simple random sample.
Hence, the true statement is (b)
Read more about random sampling at:
brainly.com/question/1334729
Ans: D
differentiate sinx=cosx and differentiate x=1
:)
Answer:
65°
Step-by-step explanation:
Radii CA and CB are perpendicular to tangent lines AT and BT, so
![\angle CAT=\angle CBT=90^{\circ}](https://tex.z-dn.net/?f=%5Cangle%20CAT%3D%5Cangle%20CBT%3D90%5E%7B%5Ccirc%7D)
Since angle BAT is equal to 65°, angle CAB has measure
![\angle CAB=90^{\circ}-65^{\circ}=25^{\circ}.](https://tex.z-dn.net/?f=%5Cangle%20CAB%3D90%5E%7B%5Ccirc%7D-65%5E%7B%5Ccirc%7D%3D25%5E%7B%5Ccirc%7D.)
Consider triangle ACB. This triangle is isosceles, because CA=CB as radii of the circle. Two angles adjacent to the base are congruent, thus
![\angle CBA=\angle CAB=25^{\circ}](https://tex.z-dn.net/?f=%5Cangle%20CBA%3D%5Cangle%20CAB%3D25%5E%7B%5Ccirc%7D)
The sum of the measures of all interior angles in triangle is always 180°, so
![\angle CAB+\angle CBA+\angle ACB=180^{\circ}\\ \\25^{\circ}+25^{\circ}+\angle ACB=180^{\circ}\\ \\\angle ACB=130^{\circ}](https://tex.z-dn.net/?f=%5Cangle%20CAB%2B%5Cangle%20CBA%2B%5Cangle%20ACB%3D180%5E%7B%5Ccirc%7D%5C%5C%20%5C%5C25%5E%7B%5Ccirc%7D%2B25%5E%7B%5Ccirc%7D%2B%5Cangle%20ACB%3D180%5E%7B%5Ccirc%7D%5C%5C%20%5C%5C%5Cangle%20ACB%3D130%5E%7B%5Ccirc%7D)
Angle ACB is central angle subtended on the minor arc AB, angle APB is inscribed angle subtended on the same minor arc AB. The measure of inscribed angle is half the measure of central angle subtended on the same arc, so
![x=\angle APB=\dfrac{1}{2}\cdot 130^{\circ}=65^{\circ}](https://tex.z-dn.net/?f=x%3D%5Cangle%20APB%3D%5Cdfrac%7B1%7D%7B2%7D%5Ccdot%20130%5E%7B%5Ccirc%7D%3D65%5E%7B%5Ccirc%7D)
This involves quite a lot of arithmetic to do manually.
The first thing you do is to make the first number in row 2 = to 0.
This is done by R2 = -3/2 R1 + R2
so the matrix becomes
( 2 1 1) ( -3 )
( 0 -13/2 3/2) (1/2 )
(5 -1 2) (-2)
Next step is to make the 5 in row 5 = 0
then the -1 must become zero
You aim for the form
( 1 0 0) (x)
(0 1 0) (y)
(0 0 1) ( z)
x , y and z will be the required solutions.