Answer:
f(x) = x² + 8 - 16x
= x² - 16x + 8
= (x² - 16x + 64) - 64 + 8
= (x + 8)² - 56
Answer:
a) 27 m/s
b) 30 m/s
c) i) 3
ii) Deceleration
Step-by-step explanation:
The question is not complete, the correct question is given as:
The graph shows information about the speed of a vehicle during the final 50 seconds of a journey. At the start of the 50 seconds the speed is k metres per second. The distance travelled during the 50 seconds is 1.35 kilometres.
(a) Work out the average speed of the vehicle during the 50 seconds
(b) Work out the value of k.
(c) (i) Calculate the gradient of the graph in the final 10 seconds of the journey
(ii) Describe what this gradient represents
Answer:
The graph is attached. The total time = 50 seconds, total distance = 1.35 km = 1350 m
a) The average speed is the ratio of the total distance traveled to the total time taken to cover this distance. The average speed is given by the formula:

b) From the graph, the total distance covered is the area of the graph. The graph is made up of a rectangle and triangle, the area of the graph is equal to the sum of area of rectangle and area of triangle.
c) i) The gradient in the last 10 seconds is the ratio of change in speed to change in time

ii) Since the gradient is negative it means it is deceleration. That is in the in the last 10 seconds the vehicle decelerates at a rate of 3 m/s²
Answer:
a) 0.023
b) 0.286
c) 10 students will be unable to complete the exam inthe allotted time.
Step-by-step explanation:
We are given the following information in the question:
Mean, μ = 80 minutes
Standard Deviation, σ = 10 minutes
We are given that the distribution of time to complete an exam is a bell shaped distribution that is a normal distribution.
Formula:

a) P(completing the exam in one hour or less)
P(x < 60)

Calculation the value from standard normal z table, we have,

b) P(complete the exam in more than 60 minutes but less than 75 minutes)

c) P(completing the exam in more than 90 minutes)
P(x > 90)


Calculation the value from standard normal z table, we have,

15.87% of children of class will require more than 90 minutes to complete the test.
Number of children =

Approximately, 10 students of class will require more than 90 minutes to complete the test.
345 mi; if you travel 69 miles per hour, and drive 5 hours, you have to multiply 69 and 5 to find how far you travel in 5-- 69 times 5 is 345.
The equation to solve for angle 1 is reliant upon the fact that the measure of an exterior angle is equal to the sum of its interior angles. In our case, angle 1 = 38 + 70 which is 108. Now to find angle 2 we have to rely upon the fact that angles 1 and 2 are supplementary, or angle 2 = 180 - angle 1. We have angle 1 is 108 so angle 2 = 180 - 108 and angle 2 = 72