Answer:
B- y=x+5
Step-by-step explanation:
We have been given for a normal distribution the mean time it takes to walk to the bus stop is 8 minutes with a standard deviation of 2 minutes. And the mean time it takes for the bus to get to school is 20 minutes with a standard deviation of 4 minutes.
(a) Average time that it would take reach school can be obtained by adding the average times.
8+20 = 28 minutes.
(b) Standard deviation of the trip to school can be found as:

Therefore, standard deviation of the entire trip is 4.47 minutes.
(c) Let us first find z score corresponding to 30 minutes.
We need to find the probability such that 
Therefore, the required probability is 0.67.
(d) If average time to walk to school is 10 minutes, then overall average time for the trip will be 10+20 = 30 minutes.
(e) Standard deviation won't change it will remain 4.47
(f) The new probability will be:


Therefore, probability will be 0.50.
Answer:
Step-by-step explanation:
<u><em>Part B:</em></u>
The center of the circumscribed circle around a triangle is equidistant from vertices of that triangle. To find the circumcenter need to draw at least two perpendicular bisectors to the sides of the given triangle. Point of intersect of them is center of the circumscribed circle.
<u><em>Part C:</em></u>
Coordinates of the midpoint of line BC ( y = - 1 ) are
(
,
) = <em>( - 2 , - 1 )</em> and the equation of the line ⊥ to BC is <em>x = - 2</em>
Because BC is ║ to x-axis and m∠A is 90° , the center of the circle is midpoint of BC and r =
= 4
Funny, this looks like a complex graph, until you realize that the numerator can be written like (x+3)(x-9).
So really, this is a straight line f(x) = x-9.
But wait, there's a catch. x≠3, because that would divide by zero. So in your straight line, you have to draw a "hole" at (3,6)
9 quarters...................