Step-by-step explanation:
7x + 8y = -12
8y=-12-7x
y=

Answer:
0.05 = 0.5/10
or
0.05 * 10 / 10 = 0.5/10
Step-by-step explanation:
Answer:
sec(theta)=1/cos(theta)
Step-by-step explanation:
sec(theta)=1/cos(theta)
Answer:
1125 m
Step-by-step explanation:
Given equation:

where:
- h = height (in metres)
- t = time (in seconds)
<u>Method 1</u>
Rewrite the equation in vertex form by completing the square:




The vertex (15, 1125) is the turning point of the parabola (minimum or maximum point). As the leading coefficient of the given equation is negative, the parabola opens downward, and so vertex is the maximum point. Therefore, the maximum height is the y-value of the vertex: 1125 metres.
<u>Method 2</u>
Differentiate the function:

Set it to zero and solve for t:



Input found value of t into the original function and solve for h:

Therefore, the maximum height is 1125 metres.
Answer:
A.) The manager calculated mean and not standard deviation
B.) Standard deviation should be calculated with the use of formula.
Step-by-step explanation:
A.) The assumption that his customers do spend more than the national average is wrong because the standard deviation is not calculated and mean cannot be used as a substitute for standard deviation.
B.) Standard deviation tells us how value obtain from group measurement deviates from the average value or expected value of each item of observations.
When standard deviation is low, this show that the value is very close to the expected value or the average value.
If the national average value = $150 and average customer spends $160.
Deviation = 160 - 150 = 10
This is lower than $30
Or better still, the manager should make use of standard deviation formula. Which is the square root of variance.