EACH central angle = 360 / number of sides
number of sides = 360 / each central angle
number of sides = 360 / 40
number of sides = 9
Answer:
b. The student's scores on the posttest would have a smaller standard deviation.
Step-by-step explanation:
The first test is taken before the material is covered in class so we expect the standard deviation to be high because not everyone's scores would be lying close to the mean. Equal number of students mastered most, some or almost none of the material from reading the textbook based on the pretest result. this means the data is varying, so the standard deviation is large.
Whereas, after the teacher has taught the material and given the homework, they must have understood most of the material. The test they take after teaching as a post test. The results of the post test would have a smaller standard deviation as most of the students would have scored good. Hence, the student's scores on the posttest would have a smaller standard deviation.
Answer:
How far did the ship travel between the two observations of the lighthouse = 9.29
Step-by-step explanation:
the first step to answer this question is drawing the illustration as the attachment.
P is the ship, R is the light house and Q is the bearing.
PR is the distance between the ship and the light house, PR = 10.5
∠P = 42.8°, ∠Q = 59.7°
Thus, ∠R = 180° - ∠P - ∠Q
= 180° - 42.8°- 59.7°
= 77.5°
PQ is the the distance of the ship moving. We can use the sinus equation
= 
= 
PQ = (
)(sin 59.7°)
= 9.29
Hack
for y=ax^2+bx+c
the xvalue of the vertex is -b/2a
and the y value is found by subsituting that for x
so
-b/2a
h(t)=2x^2+4x+7
a=2
b=4
-b/2a=-4/(2*2)=-4/4=-1
the y value
h(-1)=2(-1)^2+4(-1)+7
h(-1)=2(1)-4+7
h(1)=2+3
h(1)=5
(-1,5) is da vertex
Answer:
The answer is D.72°
Step-by-step explanation:
hope this helps.