Answer:
Step-by-step explanation:
Both 115 and 145 mph are above the mean. Draw a normal curve and mark these speeds. 115 mph is 1 standard deviation above the mean; 130 would be 2 standard deviations above the mean; and 145 would be 3 s. d. above it.
We need to find the area under the standard normal curve between 115 and 145. This is equivalent to the area under the standard normal curve between z = 1 and z = 3.
I used my TI-83 Plus calculator's DISTR function "normalcdf(" to calculate this area: normalcdf(1, 3) = 0.1573.
The area between z = 1 and z = 3 is 0.1573. In other words, the percentage of serves that were between 115 and 145 mph was 15.73%.
Answer:

Step-by-step explanation:
Differentiating, you get ...
... x·dy +y·dx +dx +dy = 2x·dx +2y·dy
Collecting terms gives ...
... dy(x +1 -2y) = dx(2x -y -1)
... dy/dx = -(2x -y -1)/(2y -x -1)
Answer:
y ≠ 9, y ≠ 3
Step-by-step explanation:
y² -12y +27 = (y - 9) (y - 3)
Denominator ≠ 0
y ≠ 9 or y ≠ 3
Answer:a2+b2=c2
32+42=52
9+16=25
25=25
Step-by-step explanation:
Answer:
Step-by-step explanation:
hello :
the slope-intercept form is : y-(-2) = m(x-(-8)) when : m is the slope