Answer:
x = 11
Step-by-step explanation:
To find this answer, just divide 360 by 5 to find out how many times his heart beats in one minute instead of 5. Doing this will give you a final answer of 72 bpm.
The correct answer is A.
You have direct variation if x and y are modeled by the equation

In this case, m is the constant of proportionality. So, if the constant has to be 2, the equation becomes

A side note: Actually, option C has a constant of proportionality of two as well, except the roles of x and y are interchanged. I chose option A because usually you want the y = mx form, but the names of the variables are obviously meaningless.
Answer: 108 degrees
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Explanation:
Angle ABC is given to be 90 degrees. By the converse of Thales Theorem, we know that AC is a diameter of the circle.
If we draw a line from A to C, it will pass through the center of the circle.
Therefore, arc AC is 180 degrees as this is half the distance around the circle.
minor arc AD = 72
minor arc CD = x
(minor arc AD) + (minor arc CD) = arc AC
72+x = 180
72+x-72 = 180-72
x = 108
minor arc CD is 108 degrees
Answer:
The common difference is -20
Step-by-step explanation:
Simply subtract 5 from -15
-15-5 = -20