3a^2-21-1=0

Solution for 3a^2-21-1=0 equation:

Simplifying
3a2 + -21 + -1 = 0

Reorder the terms:
-21 + -1 + 3a2 = 0

Combine like terms: -21 + -1 = -22
-22 + 3a2 = 0

Solving
-22 + 3a2 = 0

Solving for variable 'a'.

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

Add '22' to each side of the equation.
-22 + 22 + 3a2 = 0 + 22

Combine like terms: -22 + 22 = 0
0 + 3a2 = 0 + 22
3a2 = 0 + 22

Combine like terms: 0 + 22 = 22
3a2 = 22

Divide each side by '3'.
a2 = 7.333333333

Simplifying
a2 = 7.333333333

Take the square root of each side:
a = {-2.708012801, 2.708012801}