Answer:

Step-by-step explanation:
Question: 5 - 7(z+1) = 7(-9-3z)
We multiply the number in front of the bracket first, since that is multiplication.
--> 5 -7z -7 = -63 - 21z
--> -7z -2 = -63 - 21z
Now, we move all the z and all the numbers to each side.
--> -7z +21z = -63 +2
--> 14z = -61
--> z = -61/14
This cannot be simplified further, so z is -61/14.
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.
See attachment although I gather this is not your question. I did the graph(s) for the function,
Im pretty sure you put the wrong picture. The slope isn't negative and there is no point O,A, or B.