Answer:
- 13x² - 19x + 23
- -16x +17
Step-by-step explanation:
1 . (4x² - 9x + 16) + (7 + 9x² - 10x)
4x² - 9x + 16 + 7 + 9x² - 10x
13x² - 19x + 23
2 . (-2x + 6) - (14x - 11)
-2x + 6 - 14x + 11
-16x +17
Answer:
12 ≠ 14
Step-by-step explanation:
(4+8)=2+(6x2)
12 = 2 + 12
12 ≠ 14.
So the equation is false.
Answer: 0.0228
Step-by-step explanation:
Given : The mean and the standard deviation of finish times (in minutes) for this event are respectively as :-

If the distribution of finish times is approximately bell-shaped and symmetric, then it must be normally distributed.
Let X be the random variable that represents the finish times for this event.
z score : 

Now, the probability of runners who finish in under 19 minutes by using standard normal distribution table :-

Hence, the approximate proportion of runners who finish in under 19 minutes = 0.0228
Answer:
I got in my answer that x < 3