Answer: cos(Θ) = (√15) / 4
Explanation:
The question states:
1) sin(Θ) = 1/4
2) 0 < Θ < π / 2
3) find cos(Θ)
This is how you solve it.
1) Use the fundamental identity (in this part I use α instead of Θ, just for facility of wirting the symbols, but they mean the same for the case).

2) From which you can find:

3) Replace sin(α) with 1/4
=>

=>

4) Given that the angle is in the first quadrant, you know that cosine is positive and the final answer is:
cos(Θ) =

.
And that is the answer.
What weight represents 39th percentile
Answer:
C. 18x+9y
Step-by-step explanation:
You didn't attach anything, but this is how you should solve this equation: given an equation
the solutions are

In your case, the values are
. If you plug these values inside the solving formula, you have

So, the two solutions are 1 and 7