80=.81t^2

Solution for 80=.81t^2 equation:

Simplifying
80 = 0.81t2

Solving
80 = 0.81t2

Solving for variable 't'.

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

Add '-0.81t2' to each side of the equation.
80 + -0.81t2 = 0.81t2 + -0.81t2

Combine like terms: 0.81t2 + -0.81t2 = 0.00
80 + -0.81t2 = 0.00

Add '-80' to each side of the equation.
80 + -80 + -0.81t2 = 0.00 + -80

Combine like terms: 80 + -80 = 0
0 + -0.81t2 = 0.00 + -80
-0.81t2 = 0.00 + -80

Combine like terms: 0.00 + -80 = -80
-0.81t2 = -80

Divide each side by '-0.81'.
t2 = 98.7654321

Simplifying
t2 = 98.7654321

Take the square root of each side:
t = {-9.9380799, 9.9380799}