0=0+(21*sin(27))*t-4.9t^2

Solution for 0=0+(21*sin(27))*t-4.9t^2 equation:

Simplifying
0 = 0 + (21sin(27)) * t + -4.9t2

Reorder the terms for easier multiplication:
0 = 0 + (21 * 27ins) * t + -4.9t2

Multiply 21 * 27
0 = 0 + (567ins) * t + -4.9t2

Remove parenthesis around (567ins)
0 = 0 + 567ins * t + -4.9t2

Multiply ins * t
0 = 0 + 567inst + -4.9t2
Remove the zero:
0 = 567inst + -4.9t2

Solving
0 = 567inst + -4.9t2

Solving for variable 'i'.

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

Add '-567inst' to each side of the equation.
0 + -567inst = 567inst + -567inst + -4.9t2
Remove the zero:
-567inst = 567inst + -567inst + -4.9t2

Combine like terms: 567inst + -567inst = 0
-567inst = 0 + -4.9t2
-567inst = -4.9t2

Divide each side by '-567nst'.
i = 0.008641975309n-1s-1t

Simplifying
i = 0.008641975309n-1s-1t