70=0.81t^2

Solution for 70=0.81t^2 equation:

Simplifying
70 = 0.81t2

Solving
70 = 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.
70 + -0.81t2 = 0.81t2 + -0.81t2

Combine like terms: 0.81t2 + -0.81t2 = 0.00
70 + -0.81t2 = 0.00

Add '-70' to each side of the equation.
70 + -70 + -0.81t2 = 0.00 + -70

Combine like terms: 70 + -70 = 0
0 + -0.81t2 = 0.00 + -70
-0.81t2 = 0.00 + -70

Combine like terms: 0.00 + -70 = -70
-0.81t2 = -70

Divide each side by '-0.81'.
t2 = 86.41975309

Simplifying
t2 = 86.41975309

Take the square root of each side:
t = {-9.296222517, 9.296222517}