Answer:
C: 
Step-by-step explanation:
Amplitude is changed by multiplying the entire trig function by a number, by default the amplitude is 1, so multiplying by 6 is necessary; eliminate A and B
Horizontal shift is going through the x axis, so it must be subtracted from the x value. This is only seen in choice C of the remaining answers.
Calculating the period isn't necessary because we already found the right answer but in case you need it in the future; the period is by default 2pi, to get to pi/4, it had to be 8 times smaller, so multiplying x and translations on x by 8 will get you the correct period.
Answer:
(5x + 6) (x + 7)
Step By Step Explanation:
Use the sum form to the product.
5
It will be 27 mins to 2 hours I think
<h3>
Answers: x = 30 and y = 150</h3>
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Explanation:
For any cyclic quadrilateral (aka inscribed quadrilateral), the opposite angles are always supplementary.
One pair of such angles is A and C
A+C = 180
x+y = 180 is one equation to form
The other pair of supplementary angles is B and D
B+D = 180
y-45+2x+15 = 180
2x+y-30 = 180
2x+y = 180+30
2x+y = 210 is the other equation to form
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So the system of equations we have is

Both equations involve 'y', with the same coefficient, so we can subtract straight down to eliminate this variable.
- The x terms subtract to x-2x = -x
- The y terms subtract to y-y = 0y = 0, so the y terms go away
- The right hand sides subtract to 180-210 = -30
We end up with -x = -30 which solves to x = 30
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Once we know x, we can determine y by plugging it into any equation involving x,y and solving for y
Let's say we picked on the first equation
x+y = 180
30+y = 180
y = 180-30
y = 150
Or we could pick on the second equation
2x+y = 210
2(30) + y = 210
60+y = 210
y = 210-60
y = 150
Only one equation is needed. However, doing both like this shows that we get the same y value, and it helps confirm the answers.