40=4.9*t^2

Solution for 40=4.9*t^2 equation:

Simplifying
40 = 4.9t2

Solving
40 = 4.9t2

Solving for variable 't'.

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

Add '-4.9t2' to each side of the equation.
40 + -4.9t2 = 4.9t2 + -4.9t2

Combine like terms: 4.9t2 + -4.9t2 = 0.0
40 + -4.9t2 = 0.0

Add '-40' to each side of the equation.
40 + -40 + -4.9t2 = 0.0 + -40

Combine like terms: 40 + -40 = 0
0 + -4.9t2 = 0.0 + -40
-4.9t2 = 0.0 + -40

Combine like terms: 0.0 + -40 = -40
-4.9t2 = -40

Divide each side by '-4.9'.
t2 = 8.163265306

Simplifying
t2 = 8.163265306

Take the square root of each side:
t = {-2.857142857, 2.857142857}