even/odd:
A function f is even if the graph of f is symmetric with respect to the y-axis. Algebraically, f is even if and only if f(-x) = f(x) for all x in the domain of f.
A function f is odd if the graph of f is symmetric with respect to the origin. Algebraically, f is odd if and only if f(-x) = -f(x) for all x in the domain of f.

solve algebra:
[MATH](scroll to solver)
enter the equation so one part is zero:
x-6x^(1/2)+4=-5
add 5
x-6x^(1/2)+9=0
enter that into the calculator
press [ENTER]
press [ALPHA][ENTER]
bam

fraction <-> decimal:
[MATH][1]: convert answer to fraction
[MATH][2]: convert answer to decimal