15=3x(x)+1

Solution for 15=3x(x)+1 equation:

Simplifying
15 = 3x(x) + 1

Multiply x * x
15 = 3x2 + 1

Reorder the terms:
15 = 1 + 3x2

Solving
15 = 1 + 3x2

Solving for variable 'x'.

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

Add '-3x2' to each side of the equation.
15 + -3x2 = 1 + 3x2 + -3x2

Combine like terms: 3x2 + -3x2 = 0
15 + -3x2 = 1 + 0
15 + -3x2 = 1

Add '-15' to each side of the equation.
15 + -15 + -3x2 = 1 + -15

Combine like terms: 15 + -15 = 0
0 + -3x2 = 1 + -15
-3x2 = 1 + -15

Combine like terms: 1 + -15 = -14
-3x2 = -14

Divide each side by '-3'.
x2 = 4.666666667

Simplifying
x2 = 4.666666667

Take the square root of each side:
x = {-2.1602469, 2.1602469}