Take an example: The salary per hour:
Assume x (variable) is the number of hours worked and assume THAT THE RATE PER HOUR IS $10, then:
If you work x hours at the hourly rate of$10, you will generate an income,
say, y that is equal the number of hours worked by the rate per hour, that is:
y = 10.x. The more hour(x) you work, the more income(y) you get.
Hence we created a relationship between y and x , or in English, between the earning and the number of hours worked.
Moreover y depends on x, if there is no x, there is no y and if x increases, y increases. However x is an INDEPENDENT variable because you can
give to x any number & y will follow
Answer:
B. 4
Step-by-step explanation:
The given function is of the form:

A is called the amplitude of the given function.
We can read from the graph that, the function ranges between:
-4 and 4
This implies that:

Therefore the amplitude of the function is 4.
Hence the value of A must be 4.
Answer: x = 20.
Step-by-step explanation:
x and (3x + 10) combine to form a right angle, shown in the diagram by the small square joining the perpendicular lines.
Right angles are 90 degrees, so you can add both angles to get 90:

The correct answer is real numbers