4) Answer is D.
Irrational numbers cannot be classified as rational numbers
5) Answer is B.
Every irrational number is a real number
6x-8=13 start off with adding 8 to 13 then 6x=21 then divide 6 to both sides getting x=3.5
When working with very large or very small numbers, scientists, mathematicians, and engineers use scientific notation to express these quantities. Scientific notation is a mathematical abbreviation, based on the idea that it is easier to read an exponent than to count many zeros in a number. Very large or very small numbers need less space when written in scientific notation because the position values are expressed as powers of 10. Calculations with long numbers are easier to do when using scientific notation
That number would be 6.
Since 5^2 = 25 and 6^2 = 36, we can see that the only possible whole number between sqrt(27) and sqrt(39) has to be 6.
