Answer:
Match it with x and y method
Step-by-step explanation:
Answer:
-0.555
Step-by-step explanation:
The terminal point of the vector in this problem is
(-2,-3)
So, it is in the 3rd quadrant.
We want to find the angle
that gives the direction of this vector.
We can write the components of the vector along the x- and y- direction as:
![v_x = -2\\v_y = -3](https://tex.z-dn.net/?f=v_x%20%3D%20-2%5C%5Cv_y%20%3D%20-3)
The tangent of the angle will be equal to the ratio between the y-component and the x-component, so:
![tan \theta = \frac{v_y}{v_x}=\frac{-3}{-2}=1.5\\\theta=tan^{-1}(1.5)=56.3^{\circ}](https://tex.z-dn.net/?f=tan%20%5Ctheta%20%3D%20%5Cfrac%7Bv_y%7D%7Bv_x%7D%3D%5Cfrac%7B-3%7D%7B-2%7D%3D1.5%5C%5C%5Ctheta%3Dtan%5E%7B-1%7D%281.5%29%3D56.3%5E%7B%5Ccirc%7D)
However, since we are in the 3rd quadrant, the actual angle is:
![\theta=180^{\circ} + 56.3^{\circ} = 236.3^{\circ}](https://tex.z-dn.net/?f=%5Ctheta%3D180%5E%7B%5Ccirc%7D%20%2B%2056.3%5E%7B%5Ccirc%7D%20%3D%20236.3%5E%7B%5Ccirc%7D)
So now we can find the cosine of the angle, which will be negative:
![cos \theta = cos(236.3^{\circ})=-0.555](https://tex.z-dn.net/?f=cos%20%5Ctheta%20%3D%20cos%28236.3%5E%7B%5Ccirc%7D%29%3D-0.555)
Answer:
The vertex (h,k) is (-4,-7).
Step-by-step explanation:
I assume you are looking for the vertex
.
The vertex form of a quadratic is
where the vertex is (h,k) and a tells us if the parabola is open down (if a<0) or up (if a>0). a also tells us if it is stretched or compressed.
Anyways if you compare
to
, you should see that
.
So the vertex (h,k) is (-4,-7).
Answer:
$34.40
Step-by-step explanation:
this equation has 3 steps
1. to find out how much the dvds cost without any discount or tax: $40
2. the price of the dvds with the 20% discount, which can be found with cross-multiplication making the price after discount $32
3. the final price of the dvds with sales tax can be found also with cross-multiplication and the final answer would be 34.4
R=7s/3+k/3
Hope this helps!