Answer:

Step-by-step explanation:
Hello!
We can use the difference of square method.
<h2>Difference Of Squares (DOS)</h2>
The formula for the DOS is 
It is a simple way to factor polynomials.
The criteria:
- Has to begin and end with a perfect square
- The operation has to be subtraction
<h3>Factor:</h3>
Begins with a perfect square (x² * x²) and ends with a perfect square (4 * 4)
Warning! Watch out, there may be another DOS!
is another DOS
The x² + 4 is not a DOS because the operation is addition.
The final factored form is 
Answer:
never
Step-by-step explanation:
In a right triangle, every angle has an opposite side and an adjacent side. And there's always a hypotenuse.
The sine of an angle is the ratio of the length of the opposite side divided by the length of the hypotenuse.
The tangent ratio of an angle is the opposite side over adjacent side, it is not the sine ratio of a triangle.
For example, ABC is a right angled triangle having length of the sides are a,b,c.
So
