x^2+x=80

Simple and best practice solution for x^2+x=80 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 x^2+x=80 equation:


Simplifying
x2 + x = 80

Reorder the terms:
x + x2 = 80

Solving
x + x2 = 80

Solving for variable 'x'.

Reorder the terms:
-80 + x + x2 = 80 + -80

Combine like terms: 80 + -80 = 0
-80 + x + x2 = 0

Begin completing the square.

Move the constant term to the right:

Add '80' to each side of the equation.
-80 + x + 80 + x2 = 0 + 80

Reorder the terms:
-80 + 80 + x + x2 = 0 + 80

Combine like terms: -80 + 80 = 0
0 + x + x2 = 0 + 80
x + x2 = 0 + 80

Combine like terms: 0 + 80 = 80
x + x2 = 80

The x term is x.  Take half its coefficient (0.5).
Square it (0.25) and add it to both sides.

Add '0.25' to each side of the equation.
x + 0.25 + x2 = 80 + 0.25

Reorder the terms:
0.25 + x + x2 = 80 + 0.25

Combine like terms: 80 + 0.25 = 80.25
0.25 + x + x2 = 80.25

Factor a perfect square on the left side:
(x + 0.5)(x + 0.5) = 80.25

Calculate the square root of the right side: 8.958236434

Break this problem into two subproblems by setting 
(x + 0.5) equal to 8.958236434 and -8.958236434.

Subproblem 1

x + 0.5 = 8.958236434 Simplifying x + 0.5 = 8.958236434 Reorder the terms: 0.5 + x = 8.958236434 Solving 0.5 + x = 8.958236434 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-0.5' to each side of the equation. 0.5 + -0.5 + x = 8.958236434 + -0.5 Combine like terms: 0.5 + -0.5 = 0.0 0.0 + x = 8.958236434 + -0.5 x = 8.958236434 + -0.5 Combine like terms: 8.958236434 + -0.5 = 8.458236434 x = 8.458236434 Simplifying x = 8.458236434

Subproblem 2

x + 0.5 = -8.958236434 Simplifying x + 0.5 = -8.958236434 Reorder the terms: 0.5 + x = -8.958236434 Solving 0.5 + x = -8.958236434 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-0.5' to each side of the equation. 0.5 + -0.5 + x = -8.958236434 + -0.5 Combine like terms: 0.5 + -0.5 = 0.0 0.0 + x = -8.958236434 + -0.5 x = -8.958236434 + -0.5 Combine like terms: -8.958236434 + -0.5 = -9.458236434 x = -9.458236434 Simplifying x = -9.458236434

Solution

The solution to the problem is based on the solutions from the subproblems. x = {8.458236434, -9.458236434}

See similar equations:

| (5q+4)(9+7)(15-3q)=0 | | m-(-4)=16 | | 7x+16=x | | -((x^8)/(x^(-16)))^2 | | 6x-15=9x+18 | | x+13/4=-7/4 | | (12x-1)(2x-5)= | | 3x+4x^2-5x-7x^2= | | 7x+16= | | 82+1/3(x)=x | | 12(p+2)=9(p+3) | | 80/15 | | -60+(-6)0= | | -9x=-180 | | 6(3a-b)-6(8b-4a)= | | 11x+4=-128 | | 10y-5y= | | 1/2i^3 | | m/(-45)=-8 | | 2x-3(-6)=14 | | 40-8n=-4(3n-5) | | 55=x+41 | | 7x+2y-3x=4 | | 75=2g+3g | | 5x-10y=-8 | | y=-3/2(-1.5)+9 | | 34=x+23 | | 4w+6k+3w+2+k= | | 3-4x=5x+3 | | j+(-61)=2 | | 7y^2-7y+15-13y^2-7y+5= | | 4+5*5-2*(3-5)= |

Equations solver categories