If you recall soh-cah-toa, tangent is equal to the opposite length divided by the adjacent length so it is true.
Answer:
There you go.
Step-by-step explanation:
Please do tell me if it's wrong.
A ) cos² x · 1 / sin x - 1 / sin x = - sin x
cos² x - 1 / sin x = - sin x
- sin² x / sin x = - sin x
- sin x = - sin x ( correct )
B ) sin x ( cos x / sin x + sin x / cos x ) = 1 / cos x
sin x · ( cos² x + sin²x ) / sin x cos x = 1 / cos x
sin x · 1 / sin x cos x = 1 / cos x
1 / cos x = 1 / cos x ( correct )
C ) cos² x - sin² x = 1 - 2 sin² x
1 - sin² x - sin² x = 1 - 2 sin² x
1 - 2 sin² x = 1 - 2 sin² x ( correct )
D ) 1/sin²x + 1/ cos²x = 1
cos²x + sin² x / sin² x cos² x = 1
1 / cos² x sin² x = 1
cos²x sin² x ≠ 1
Answer: D ) is not an identity.
The value of y for the system of equation is -1/2 .
<h3>What is a System of Equation ?</h3>
A system of equation is a set of equation that have common solution
The set of equation given is
3x+4y=4
2x−4y=6
To solve the system , Elimination method will be used
Add equation 1 and 2 to eliminate y
5x = 10
x = 2
Substitute the value of x in equation 1 to determine y
3x +4y = 4
6 + 4y = 4
4y = -2
y = -1/2
Therefore the value of y for the system of equation is -1/2 .
To know more about System of Equation
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