h(0)=3-x^2

Solution for h(0)=3-x^2 equation:

Simplifying
h(0) = 3 + -1x2

Reorder the terms for easier multiplication:
0h = 3 + -1x2

Anything times zero is zero.
0h = 3 + -1x2

Solving
0 = 3 + -1x2

Solving for variable 'x'.

Move all terms containing x to the left, all other terms to the right.

Add 'x2' to each side of the equation.
0 + x2 = 3 + -1x2 + x2
Remove the zero:
x2 = 3 + -1x2 + x2

Combine like terms: -1x2 + x2 = 0
x2 = 3 + 0
x2 = 3

Simplifying
x2 = 3

Take the square root of each side:
x = {-1.732050808, 1.732050808}