(3a-7)^2
1. 9a^2-21a-21a+49
2. 3a(3a-7)-7(3a-7)
3. (3a-7)(3a-7)
4. Combine like terms
Answer:
4i√5
Step-by-step explanation:

Answer:
The correct option is B
Step-by-step explanation:
From the question we are told that
The sample size is 
The proportion that choose to vaccinate the teen boys is 
considering the first statement
The 95% confidence interval is 12% ± the margin of error*standard deviation is false because
The 95% confidence interval is is %12 ± the margin of error
considering the second statement
The confidence interval should not be calculated due to the small sample size is true because from the central limit theorem
np = 64 * 0.12 = 7.68
and this value is less than 10 hence the confidence interval should not be calculated
considering the third statement
A 99% confidence interval will be smaller than the 90% confidence interval is false
This is because as the confidence level increase (for example from 90% to 99%) the margin of error increase which increases the confidence interval
If we draw in OX, OY, OZ we have two congruent right triangles, right angles at the tangent points.
We know XOZ is 132 degrees, which is the meaning of the arc measure
So YOX is half that, 66 degrees.
That leaves 180 - 90 - 66 = 24 degrees for OYX
Angle Y aka XYZ is double that, 48 degrees.
Answer: C