Using a system of equations, it is found that the correct option is:
A) 1389x+1660y=787x+1121y.
<h3>What is a system of equations?</h3>
A system of equations is when two or more variables are related, and equations are built to find the values of each variable.
In this problem, considering the amounts in each olympics(1389 men and 787 women participated on the 19th, 1660 men and 1121 women in the 22th), the system is:
A) 1389x+1660y=787x+1121y.
More can be learned about a system of equations at brainly.com/question/24342899
Answer:
2) 162°, 72°, 108°
3) 144°, 54°, 126°
Step-by-step explanation:
1) Multiply the equation by 2sin(θ) to get an equation that looks like ...
sin(θ) = <some numerical expression>
Use your knowledge of the sines of special angles to find two angles that have this sine value. (The attached table along with the relations discussed below will get you there.)
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2, 3) You need to review the meaning of "supplement".
It is true that ...
sin(θ) = sin(θ+360°),
but it is also true that ...
sin(θ) = sin(180°-θ) . . . . the supplement of the angle
This latter relation is the one applicable to this question.
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Similarly, it is true that ...
cos(θ) = -cos(θ+180°),
but it is also true that ...
cos(θ) = -cos(180°-θ) . . . . the supplement of the angle
As above, it is this latter relation that applies to problems 2 and 3.
All of given options contain quadratic functions. One way to determine the extreme value is squaring the expression with variable x.
Option B contain the expression where you can see perfect square. Thus, equation
(choice B) reveals its extreme value without needing to be altered.
To determine the extreme value of this equation, you should substitute x=2 (x-value that makes expression in brackets equal to zero) into the function notation:
The extreme value of this equation has a minimum at the point (2,5).
Answer: -2x² - 15x + 11
Step-by-step explanation: