Answer:
Resulting equation will be 5x²=36.
Step-by-step explanation:
The given equations are 5y = 10x-----(1)
and x²+y²=36------(2)
Now we substitute the value of y from equation (1) into equation (2).
5y = 10x ⇒ y = 2x
Then equation (2) will be x²+(2x)²=36
x²+4x²=36 ⇒ 5x² = 36
So the equation after substitution of the value of y from equation 1 will be 5x² = 36.
Answer:
The possible values of x are 90°, 30° and 150°.
Step-by-step explanation:
Given that,
sin(2x) = cos(x) where 0° ≤ x < 180°
We know that, sin(2x) = 2 sinx cosx
2 sinx cosx = cosx
Subtract cosx on both sides
2 sinx cosx - cosx = 0
cosx (2sinx-1)=0
It means, cosx = 0 and (2sin x -1 ) = 0
cos x = cos0 and sinx = 1/2
x = 90° and x = 30°, 150°
Hence, the possible values of x are 90°, 30° and 150°.
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