Observation one
From the markings on the diagram <1 = 60o The left triangle is at least isosceles. Therefore equal sides produce equal angles opposite them.
Now we have accounted for 2 angles that are equal (each is 60 degrees) and add up to 120 degrees. The third angle (angle 2) is found from this equation.
<1 + 60 + <2 = 180 degrees. All triangles have 180 degrees.
60 + 60 + <2 = 180
Observation 2
<2 = 60 degrees.
120 + <2 = 180
m<2 = 180 - 120
m<2 = 60 degrees.
Observation 3
m<3 = 120
<2 and <3 are supplementary.
Any 2 angles on the same straight line are supplementary
60 + <3 = 180
<3 = 180 - 60
<3 = 120
Observation 4
m<4 = 40 degrees.
All triangles have 180 degrees. No exceptions.
m<4 + 20 +m<3 = 180
m<4 + 20 + 120 = 180
m<4 + 140 = 180
m<4 = 180 - 140
m<4 = 40
C is the answer because it is
Answer: А. On average, the number of students going to an office hour varies from the mean by about 2.2 students
Step-by-step explanation:
The standard deviation is a measure of spread, which gives how values deviate from the average or mean value of a particular distribution. Hence, the standard deviation is usually defined about the average value of a distribution.
Therefore, for a certain random variable representing the number of student who visits office hours, the standard deviation will be defined about the average or mean value of the random variable Q.
Thus, stated as ; number of students going to an office hour varies from the mean by 2.2 on average.
Hello here is a solution:
So basically you want to isolate only one of the variable on one side so
y=-9+x^2
add 9 to both sides
y+9=x^2
square root both sides

x=