Answer: 
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Explanation:
Use the pythagorean trig identity
and plug in the fact that 
Isolating sine leads to
. I'm skipping the steps here, but let me know if you need to see them.
The result is negative because we're in quadrant 4, when y < 0 so it's when sine is negative.
Therefore,

The answers are : A and C
Answer:

Step-by-step explanation:
Area of a circle with radius
: 
Circumference of a sector with radius
: 
Area of sector with angle
:
.
Arc length of sector with angle
: 
Using these equations, we get the following information:
Area of circle: 
Circumference of a circle: 
Area of sector: 
Arc length of sector: 
First find the slope, take derivative of both sides with respect to x.
2y dy/dx=3x^2+6x
solve for dy/dx
dy/dx=[3x^2+6x]/2y
plug in given vales of (1,2(
dy/dx=9/4
now you have everything you need to plug into point slope form
y-2=(9/4)(x-1)
answer is y=(9/4)x+(1/4)
Answer:
1. Given
2, Exterior sides on opposite rays
3. Definition of supplementary angles
4. If lines are ||, corresponding angles are equal
5. Substitution
Step-by-step explanation:
For the first one, it is given as shown in the problem. Also in the figure you can see that line s is parallel to line t.
2. ∠5 and ∠7 are adjacent, they share a common side. Their non-common side are rays that go in a direction opposite of each other. Also you can see that they form a straight line, which means that they are supplementary.
3. Supplementary angles simply put are angles that sum up to 180°. You know this for sure because of proof 2, specifically the part that they form a straight line. The measure of a straight line is 180°.
4. Corresponding angles are congruent. These are angles that have the same relative position when a line is intersected by parallel lines. You have other example in the figure like ∠2 and ∠6; ∠3 and ∠7.
5. This is substitution because ∠1 substituted ∠5 in this case. Since ∠1 is equal to ∠5, then it can substitute it in the equation given in step 3. This means that ∠1 and ∠7 are supplementary as well.