The <em><u>correct answer</u></em> is:
c)75.4 to 94.6
Explanation:
The formula for a confidence interval is:
,
where μ is the mean, z is the z-score associated with the level of confidence we want, σ is the standard deviation, and n is the sample size.
Our mean is 85, our standard deviation is 12, our sample size is 6, and since we want 95% confidence, our z-score is 1.96:
Given:
Line a is perpendicular to line b .
Line a passes through the points (1,-8) and (9,-12) .
Line b passes through the point (-8, -16).
To find:
The equation of b.
Solution:
Line a passes through the points (1,-8) and (9,-12) . So, slope of line a is
Product of slopes of two perpendicular lines is -1.
Slope of line b is 2.
If a line passing through a point with slope m, then equation of line is
Line b passing through (-8,-16) with slope 2. So, equation of line b is
Subtract 16 from both sides.
Therefore, the equation of line b is .