Answer:
C) π/6
Step-by-step explanation:
The area under the curve from x=-π/2 to x=k is 3 times the area under the curve from x=k to x=π/2.

Graph: desmos.com/calculator/mezlen9hb4
Because it's decreasing, you use the formula (1-x/100)y with x the percentage decreased which is here 40, and y the number decreased which is here 90
So we get
(1-40/100) * 90
(100/100 - 40/100) * 90
60/100 * 90
5400/100
54
So 90 decreased by 40% is 54
Hope this Helps :)
The measurement of ∠B is 168°
Given,
In the question:
Angle A and Angle B are supplementary angles.
If mA (x - 9)° and m/B= (7x + 21)°
To find the measure of ∠B
Now, According to the question;
What are supplementary angles?
Two angles are Supplementary when they add up to 180 degrees.
Now, ∠A+∠B = 180°
So,
⇒(x - 9)˚+(7x + 21)°=180°
=> 8x +12 = 180°
=> 8x = 180° - 12
=> 8x = 168
=> x = 168/8
=> x = 21
For the measure of ∠B :
∠B = (7x + 21)
∠B = 7 x 21 + 21
∠B = 168°
Hence, The measurement of ∠B is 168°
Learn more about Supplementary angles at:
brainly.com/question/13045673
#SPJ1
The answer is: 90° .
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c is the correct answer of this question