D. All irrational numbers are rational numbers.
I attached the diagram my teacher showed us when we learned about this. I think it makes it a lot less confusing.
Hope this helps :)
2x + 3 = 9 Move all terms not containing x to the right side of the equation.
2x = 6 Divide each term by 2 and simplify.
x=3
The answer would be B C E hope this helps :)
Altitudes make right angles so it is C