20t^2+t-21=0

Solution for 20t^2+t-21=0 equation:

Simplifying
20t2 + t + -21 = 0

Reorder the terms:
-21 + t + 20t2 = 0

Solving
-21 + t + 20t2 = 0

Solving for variable 't'.

Factor a trinomial.
(-21 + -20t)(1 + -1t) = 0

Subproblem 1
Set the factor '(-21 + -20t)' equal to zero and attempt to solve:

Simplifying
-21 + -20t = 0

Solving
-21 + -20t = 0

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

Add '21' to each side of the equation.
-21 + 21 + -20t = 0 + 21

Combine like terms: -21 + 21 = 0
0 + -20t = 0 + 21
-20t = 0 + 21

Combine like terms: 0 + 21 = 21
-20t = 21

Divide each side by '-20'.
t = -1.05

Simplifying
t = -1.05
Subproblem 2
Set the factor '(1 + -1t)' equal to zero and attempt to solve:

Simplifying
1 + -1t = 0

Solving
1 + -1t = 0

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

Add '-1' to each side of the equation.
1 + -1 + -1t = 0 + -1

Combine like terms: 1 + -1 = 0
0 + -1t = 0 + -1
-1t = 0 + -1

Combine like terms: 0 + -1 = -1
-1t = -1

Divide each side by '-1'.
t = 1

Simplifying
t = 1
Solution
t = {-1.05, 1}