It is so easy if you use your calculator: ±7.937
The square roots are irrational.
Rational zero test cannot be used to find irrational roots as well as rational roots.
No.
Yes
Not always. For example: sqrt(2)+(-sqrt(2))=0 which is not irrational.
The square roots of 163 are irrational.
The square roots of 84 are irrational.
The square roots of 50 are irrational.
There is no special symbol for an irrational number. However, it is known that many square roots, cubic roots, etc., as well as some special numbers such as pi and e, are irrational.
The square roots are irrational.
Most of them are.
Irrational numbers can be roots because they are solutions to certain mathematical equations. For example, the square root of 2 is an irrational number that is a solution to the equation x^2 = 2. Similarly, other irrational numbers can be roots of different equations depending on their mathematical properties.