13.7=13.7t-4.9t^2

Solution for 13.7=13.7t-4.9t^2 equation:

Simplifying
13.7 = 13.7t + -4.9t2

Solving
13.7 = 13.7t + -4.9t2

Solving for variable 't'.

Reorder the terms:
13.7 + -13.7t + 4.9t2 = 13.7t + -13.7t + -4.9t2 + 4.9t2

Combine like terms: 13.7t + -13.7t = 0.0
13.7 + -13.7t + 4.9t2 = 0.0 + -4.9t2 + 4.9t2
13.7 + -13.7t + 4.9t2 = -4.9t2 + 4.9t2

Combine like terms: -4.9t2 + 4.9t2 = 0.0
13.7 + -13.7t + 4.9t2 = 0.0

Begin completing the square.  Divide all terms by
4.9 the coefficient of the squared term: 

Divide each side by '4.9'.
2.795918367 + -2.795918367t + t2 = 0

Move the constant term to the right:

Add '-2.795918367' to each side of the equation.
2.795918367 + -2.795918367t + -2.795918367 + t2 = 0 + -2.795918367

Reorder the terms:
2.795918367 + -2.795918367 + -2.795918367t + t2 = 0 + -2.795918367

Combine like terms: 2.795918367 + -2.795918367 = 0.000000000
0.000000000 + -2.795918367t + t2 = 0 + -2.795918367
-2.795918367t + t2 = 0 + -2.795918367

Combine like terms: 0 + -2.795918367 = -2.795918367
-2.795918367t + t2 = -2.795918367

The t term is -2.795918367t.  Take half its coefficient (-1.397959184).
Square it (1.954289880) and add it to both sides.

Add '1.954289880' to each side of the equation.
-2.795918367t + 1.954289880 + t2 = -2.795918367 + 1.954289880

Reorder the terms:
1.954289880 + -2.795918367t + t2 = -2.795918367 + 1.954289880

Combine like terms: -2.795918367 + 1.954289880 = -0.841628487
1.954289880 + -2.795918367t + t2 = -0.841628487

Factor a perfect square on the left side:
(t + -1.397959184)(t + -1.397959184) = -0.841628487

Can't calculate square root of the right side.

The solution to this equation could not be determined.