Answer: y = -14/9(x + 4)^2 + 7
Step-by-step explanation:
The given roots of the quadratic function is (-1, -7)
The vertex is at (-4, 7)
The formula is
y = a(x - h)^2 + k
The vertex is (h, k)
Comparing with the given vertex, (-4, 7), h = -4 and k = 7
Substituting into the formula
y = a(x - h)^2 + k, it becomes
y = a(x - - 4)^2 + 7
y = a(x + 4)^2 + 7
From the roots given (-1, -7)
x = -1 and y = -7
Substituting x = -1 and y = -7 into the equation,
y = a(x + 4)^2 + 7, it becomes
-7 = a(-1+4)^2 + 7
-7 = a(3^2 ) + 7
- 7 = 9a + 7
-7-7 = 9a
9a = -14
a = -14/9
Substituting a = - 14/9 into the equation, it becomes
y = -14/9(x + 4)^2 + 7
Answer:
225 students scored 65 or better and 75 students scored 88 or better.
Step-by-step explanation:
We are given that The five-number summary for the scores of 300 nursing students are given :
Minimum = 40
Median = 82
Maximum = 100
is the first quartile and is the median of the lower half of the data set. 25% of the numbers in the data set lie below and about 75% lie above .
is the third quartile and is the median of the upper half of the data set. 75% of the numbers in the data set lie below and about 25% lie above
i) .About how many students scored 65 or better?
Since we know that 75% lie above .
So, Number of students scored 65 or better = 
ii)About how many students scored 88 or better?
Since we know that 25% lie above
So, Number of students scored 88 or better = 
Hence 225 students scored 65 or better and 75 students scored 88 or better.
