Answer:
C. 17.6
General Formulas and Concepts:
<u>Math</u>
<u>Pre-Algebra</u>
Order of Operations: BPEMDAS
- Brackets
- Parenthesis
- Exponents
- Multiplication
- Division
- Addition
- Subtraction
Equality Properties
- Multiplication Property of Equality
- Division Property of Equality
- Addition Property of Equality
- Subtraction Property of Equality<u>
</u>
<u>Trigonometry</u>
- [Right Triangles Only] SOHCAHTOA
- [Right Triangles Only] tanθ = opposite over adjacent
Step-by-step explanation:
<u>Step 1: Identify Variables</u>
Angle θ = 40°
Opposite Leg = <em>x</em>
Adjacent Leg = 21
<u>Step 2: Solve for </u><em><u>x</u></em>
- Substitute in variables [tangent]:

- [Multiplication Property of Equality] Isolate <em>x</em>:

- Rewrite:

- Evaluate:

- Round:

You find the eigenvalues of a matrix A by following these steps:
- Compute the matrix
, where I is the identity matrix (1s on the diagonal, 0s elsewhere) - Compute the determinant of A'
- Set the determinant of A' equal to zero and solve for lambda.
So, in this case, we have
![A = \left[\begin{array}{cc}1&-2\\-2&0\end{array}\right] \implies A'=\left[\begin{array}{cc}1&-2\\-2&0\end{array}\right]-\left[\begin{array}{cc}\lambda&0\\0&\lambda\end{array}\right]=\left[\begin{array}{cc}1-\lambda&-2\\-2&-\lambda\end{array}\right]](https://tex.z-dn.net/?f=A%20%3D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D1%26-2%5C%5C-2%260%5Cend%7Barray%7D%5Cright%5D%20%5Cimplies%20A%27%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D1%26-2%5C%5C-2%260%5Cend%7Barray%7D%5Cright%5D-%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D%5Clambda%260%5C%5C0%26%5Clambda%5Cend%7Barray%7D%5Cright%5D%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D1-%5Clambda%26-2%5C%5C-2%26-%5Clambda%5Cend%7Barray%7D%5Cright%5D)
The determinant of this matrix is

Finally, we have

So, the two eigenvalues are

I hope this helps you
QR=WS=2.93
RS=QW =2.04
QS=XR =2.28
RS=XQ=2.04
SY=QR =2.93
RY=QS =2.28
XY=XR+RY=2.28+2.28=4.56
XW=XQ+QW=2.04+2.04=4.08
WY=WS+SY=2.93+2.93=5.86
Perimeter of XYW=XW+WY+XY
Perimeter of XYW=4.08+5.86+4.56
Perimeter of XYW =14.5