3x=x^2-20

Simple and best practice solution for 3x=x^2-20 equation. Check how easy it is, and learn it for the future. Our solution is simple, and easy to understand, so don`t hesitate to use it as a solution of your homework.

If it's not what You are looking for type in the equation solver your own equation and let us solve it.

Solution for 3x=x^2-20 equation:


Simplifying
3x = x2 + -20

Reorder the terms:
3x = -20 + x2

Solving
3x = -20 + x2

Solving for variable 'x'.

Reorder the terms:
20 + 3x + -1x2 = -20 + x2 + 20 + -1x2

Reorder the terms:
20 + 3x + -1x2 = -20 + 20 + x2 + -1x2

Combine like terms: -20 + 20 = 0
20 + 3x + -1x2 = 0 + x2 + -1x2
20 + 3x + -1x2 = x2 + -1x2

Combine like terms: x2 + -1x2 = 0
20 + 3x + -1x2 = 0

Begin completing the square.  Divide all terms by
-1 the coefficient of the squared term: 

Divide each side by '-1'.
-20 + -3x + x2 = 0

Move the constant term to the right:

Add '20' to each side of the equation.
-20 + -3x + 20 + x2 = 0 + 20

Reorder the terms:
-20 + 20 + -3x + x2 = 0 + 20

Combine like terms: -20 + 20 = 0
0 + -3x + x2 = 0 + 20
-3x + x2 = 0 + 20

Combine like terms: 0 + 20 = 20
-3x + x2 = 20

The x term is -3x.  Take half its coefficient (-1.5).
Square it (2.25) and add it to both sides.

Add '2.25' to each side of the equation.
-3x + 2.25 + x2 = 20 + 2.25

Reorder the terms:
2.25 + -3x + x2 = 20 + 2.25

Combine like terms: 20 + 2.25 = 22.25
2.25 + -3x + x2 = 22.25

Factor a perfect square on the left side:
(x + -1.5)(x + -1.5) = 22.25

Calculate the square root of the right side: 4.716990566

Break this problem into two subproblems by setting 
(x + -1.5) equal to 4.716990566 and -4.716990566.

Subproblem 1

x + -1.5 = 4.716990566 Simplifying x + -1.5 = 4.716990566 Reorder the terms: -1.5 + x = 4.716990566 Solving -1.5 + x = 4.716990566 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '1.5' to each side of the equation. -1.5 + 1.5 + x = 4.716990566 + 1.5 Combine like terms: -1.5 + 1.5 = 0.0 0.0 + x = 4.716990566 + 1.5 x = 4.716990566 + 1.5 Combine like terms: 4.716990566 + 1.5 = 6.216990566 x = 6.216990566 Simplifying x = 6.216990566

Subproblem 2

x + -1.5 = -4.716990566 Simplifying x + -1.5 = -4.716990566 Reorder the terms: -1.5 + x = -4.716990566 Solving -1.5 + x = -4.716990566 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '1.5' to each side of the equation. -1.5 + 1.5 + x = -4.716990566 + 1.5 Combine like terms: -1.5 + 1.5 = 0.0 0.0 + x = -4.716990566 + 1.5 x = -4.716990566 + 1.5 Combine like terms: -4.716990566 + 1.5 = -3.216990566 x = -3.216990566 Simplifying x = -3.216990566

Solution

The solution to the problem is based on the solutions from the subproblems. x = {6.216990566, -3.216990566}

See similar equations:

| 7n+16=9 | | 12-2x=x+3 | | X^(1/2)=x-6 | | y=sinx/tanx-1 | | 42/15= | | 2/5(r | | -5d-6=2.5 | | 4x+28y=-52 | | -20-20x+15x^2=0 | | (4-w)(5w-8)=0 | | -20-20x+15x^2=o | | 6y-5y-2=5 | | 12a+3b=1 | | 18u^2+15u-42=0 | | 8=2/5y | | 1-2x=27 | | 4y/3=48 | | -y+1=5 | | 2x+1-2x=35 | | x^(1/2)=x-20 | | 56=9y+4y+6 | | 6u^2+27u-15=0 | | 25+0.50x=112.00 | | -g=-5 | | 25-0.50=112.00 | | 0.36(6)+0.04x=0.12(36+x) | | 5/4r-5=1/4r | | 21=r-5 | | 0.36(6)+0.04=0.12(36+x) | | (9/64)(9/9) | | 11(v+2)-2v=3(3v+3)-10 | | 8=m+8 |

Equations solver categories