Answer:
- 33 1/3 liters of 30%
- 16 2/3 liters of 45%
Step-by-step explanation:
Let x represent the liters of 45% solution needed. Then the amount of HCl in the mix is ...
0.45x +0.30(50 -x) = 0.35(50)
0.15x = 0.05(50) . . . . . simplify, subtract 0.30(50)
x = (0.05/0.15)(50) = 50/3 = 16 2/3 . . . liters of 45% HCl
33 1/3 liters of 30% and 16 2/3 liters of 45% HCl are needed.
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<em>Comment on the solution</em>
You may notice that the general solution to a mixture problem of this sort is that the fraction of the mix that is the highest contributor is ...
(mix % - low %) / (high % - low %) = (.35 -.30) / (.45 -.30) = .05/.15 = 1/3
Answer:
Option B is correct
the degree of rotation is, ![-90^{\circ}](https://tex.z-dn.net/?f=-90%5E%7B%5Ccirc%7D)
Step-by-step explanation:
A rotation matrix is a matrix that is used to perform a rotation in Euclidean space.
To find the degree of rotation using a standard rotation matrix i.e,
![R = \begin{bmatrix}\cos \theta & -\sin \theta \\ \sin \theta & \cos \theta \end{bmatrix}](https://tex.z-dn.net/?f=R%20%3D%20%5Cbegin%7Bbmatrix%7D%5Ccos%20%5Ctheta%20%26%20-%5Csin%20%5Ctheta%20%5C%5C%20%5Csin%20%5Ctheta%20%26%20%5Ccos%20%5Ctheta%20%5Cend%7Bbmatrix%7D)
Given the matrix: ![\begin{bmatrix}0 & 1 \\ -1 & 0\end{bmatrix}](https://tex.z-dn.net/?f=%5Cbegin%7Bbmatrix%7D0%20%26%201%20%5C%5C%20-1%20%26%200%5Cend%7Bbmatrix%7D)
Now, equate the given matrix with standard matrix we have;
= ![\begin{bmatrix}0 & 1 \\ -1 & 0\end{bmatrix}](https://tex.z-dn.net/?f=%5Cbegin%7Bbmatrix%7D0%20%26%201%20%5C%5C%20-1%20%26%200%5Cend%7Bbmatrix%7D)
On comparing we get;
and
As,we know:
![\cos \theta = \cos(90^{\circ}) = \cos( -90^{\circ})](https://tex.z-dn.net/?f=%5Ccos%20%5Ctheta%20%3D%20%5Ccos%2890%5E%7B%5Ccirc%7D%29%20%3D%20%5Ccos%28%20-90%5E%7B%5Ccirc%7D%29)
we get;
![\theta = -90^{\circ}](https://tex.z-dn.net/?f=%5Ctheta%20%3D%20-90%5E%7B%5Ccirc%7D)
and
![\sin \theta =- \sin (90^{\circ}) = \sin ( -90^{\circ})](https://tex.z-dn.net/?f=%5Csin%20%5Ctheta%20%3D-%20%5Csin%20%2890%5E%7B%5Ccirc%7D%29%20%3D%20%5Csin%20%28%20-90%5E%7B%5Ccirc%7D%29)
we get;
![\theta = -90^{\circ}](https://tex.z-dn.net/?f=%5Ctheta%20%3D%20-90%5E%7B%5Ccirc%7D)
Therefore, the degree of rotation is, ![-90^{\circ}](https://tex.z-dn.net/?f=-90%5E%7B%5Ccirc%7D)
Answer:
i think the difference in height from the top to the bottom is 8ft
Answer:
![\large\boxed{A.\ f(x)+g(x)=9x^2-x-3}\\\boxed{B.\ f(x)-g(x)=5x^2-9x+9}\\\boxed{g(x)-f(x)=-5x^2+9x-9}](https://tex.z-dn.net/?f=%5Clarge%5Cboxed%7BA.%5C%20f%28x%29%2Bg%28x%29%3D9x%5E2-x-3%7D%5C%5C%5Cboxed%7BB.%5C%20f%28x%29-g%28x%29%3D5x%5E2-9x%2B9%7D%5C%5C%5Cboxed%7Bg%28x%29-f%28x%29%3D-5x%5E2%2B9x-9%7D)
Step-by-step explanation:
![f(x)=7x^2-5x+3,\ g(x)=2x^2+4x-6\\\\A:\\f(x)+g(x)=(7x^2-5x+3)+(2x^2+4x-6)\\f(x)+g(x)=7x^2-5x+3+2x^2+4x-6\qquad\text{combine like terms}\\f(x)+g(x)=(7x^2+2x^2)+(-5x+4x)+(3-6)\\f(x)+g(x)=9x^2-x-3](https://tex.z-dn.net/?f=f%28x%29%3D7x%5E2-5x%2B3%2C%5C%20g%28x%29%3D2x%5E2%2B4x-6%5C%5C%5C%5CA%3A%5C%5Cf%28x%29%2Bg%28x%29%3D%287x%5E2-5x%2B3%29%2B%282x%5E2%2B4x-6%29%5C%5Cf%28x%29%2Bg%28x%29%3D7x%5E2-5x%2B3%2B2x%5E2%2B4x-6%5Cqquad%5Ctext%7Bcombine%20like%20terms%7D%5C%5Cf%28x%29%2Bg%28x%29%3D%287x%5E2%2B2x%5E2%29%2B%28-5x%2B4x%29%2B%283-6%29%5C%5Cf%28x%29%2Bg%28x%29%3D9x%5E2-x-3)
![B:\\f(x)-g(x)=(7x^2-5x+3)-(2x^2+4x-6)\\f(x)+g(x)=7x^2-5x+3-2x^2-4x+6\qquad\text{combine like terms}\\f(x)-g(x)=(7x^2-2x^2)+(-5x-4x)+(3+6)\\f(x)+g(x)=5x^2-9x+9](https://tex.z-dn.net/?f=B%3A%5C%5Cf%28x%29-g%28x%29%3D%287x%5E2-5x%2B3%29-%282x%5E2%2B4x-6%29%5C%5Cf%28x%29%2Bg%28x%29%3D7x%5E2-5x%2B3-2x%5E2-4x%2B6%5Cqquad%5Ctext%7Bcombine%20like%20terms%7D%5C%5Cf%28x%29-g%28x%29%3D%287x%5E2-2x%5E2%29%2B%28-5x-4x%29%2B%283%2B6%29%5C%5Cf%28x%29%2Bg%28x%29%3D5x%5E2-9x%2B9)
![C:\\g(x)-f(x)=(2x^2+4x-6)-(7x^2-5x+3)\\g(x)-f(x)=2x^2+4x-6-7x^2+5x-3\qquad\text{combine like terms}\\g(x)-f(x)=(2x^2-7x^2)+(4x+5x)+(-6-3)\\g(x)-f(x)=-5x^2+9x-9](https://tex.z-dn.net/?f=C%3A%5C%5Cg%28x%29-f%28x%29%3D%282x%5E2%2B4x-6%29-%287x%5E2-5x%2B3%29%5C%5Cg%28x%29-f%28x%29%3D2x%5E2%2B4x-6-7x%5E2%2B5x-3%5Cqquad%5Ctext%7Bcombine%20like%20terms%7D%5C%5Cg%28x%29-f%28x%29%3D%282x%5E2-7x%5E2%29%2B%284x%2B5x%29%2B%28-6-3%29%5C%5Cg%28x%29-f%28x%29%3D-5x%5E2%2B9x-9)