-1=-.5(9.8)(x^2)

Solution for -1=-.5(9.8)(x^2) equation:

Simplifying
-1 = -0.5(9.8)(x2)

Multiply -0.5 * 9.8
-1 = -4.9x2

Solving
-1 = -4.9x2

Solving for variable 'x'.

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

Add '4.9x2' to each side of the equation.
-1 + 4.9x2 = -4.9x2 + 4.9x2

Combine like terms: -4.9x2 + 4.9x2 = 0.0
-1 + 4.9x2 = 0.0

Add '1' to each side of the equation.
-1 + 1 + 4.9x2 = 0.0 + 1

Combine like terms: -1 + 1 = 0
0 + 4.9x2 = 0.0 + 1
4.9x2 = 0.0 + 1

Combine like terms: 0.0 + 1 = 1
4.9x2 = 1

Divide each side by '4.9'.
x2 = 0.2040816327

Simplifying
x2 = 0.2040816327

Take the square root of each side:
x = {-0.451753952, 0.451753952}