x^2+2x=77

Simple and best practice solution for x^2+2x=77 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+2x=77 equation:


Simplifying
x2 + 2x = 77

Reorder the terms:
2x + x2 = 77

Solving
2x + x2 = 77

Solving for variable 'x'.

Reorder the terms:
-77 + 2x + x2 = 77 + -77

Combine like terms: 77 + -77 = 0
-77 + 2x + x2 = 0

Begin completing the square.

Move the constant term to the right:

Add '77' to each side of the equation.
-77 + 2x + 77 + x2 = 0 + 77

Reorder the terms:
-77 + 77 + 2x + x2 = 0 + 77

Combine like terms: -77 + 77 = 0
0 + 2x + x2 = 0 + 77
2x + x2 = 0 + 77

Combine like terms: 0 + 77 = 77
2x + x2 = 77

The x term is 2x.  Take half its coefficient (1).
Square it (1) and add it to both sides.

Add '1' to each side of the equation.
2x + 1 + x2 = 77 + 1

Reorder the terms:
1 + 2x + x2 = 77 + 1

Combine like terms: 77 + 1 = 78
1 + 2x + x2 = 78

Factor a perfect square on the left side:
(x + 1)(x + 1) = 78

Calculate the square root of the right side: 8.831760866

Break this problem into two subproblems by setting 
(x + 1) equal to 8.831760866 and -8.831760866.

Subproblem 1

x + 1 = 8.831760866 Simplifying x + 1 = 8.831760866 Reorder the terms: 1 + x = 8.831760866 Solving 1 + x = 8.831760866 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-1' to each side of the equation. 1 + -1 + x = 8.831760866 + -1 Combine like terms: 1 + -1 = 0 0 + x = 8.831760866 + -1 x = 8.831760866 + -1 Combine like terms: 8.831760866 + -1 = 7.831760866 x = 7.831760866 Simplifying x = 7.831760866

Subproblem 2

x + 1 = -8.831760866 Simplifying x + 1 = -8.831760866 Reorder the terms: 1 + x = -8.831760866 Solving 1 + x = -8.831760866 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '-1' to each side of the equation. 1 + -1 + x = -8.831760866 + -1 Combine like terms: 1 + -1 = 0 0 + x = -8.831760866 + -1 x = -8.831760866 + -1 Combine like terms: -8.831760866 + -1 = -9.831760866 x = -9.831760866 Simplifying x = -9.831760866

Solution

The solution to the problem is based on the solutions from the subproblems. x = {7.831760866, -9.831760866}

See similar equations:

| z-5+3=-35 | | 8x^3+14n^2+6n+1=0 | | 2(3m^2-18m)=0 | | X+(X*0.085)=125 | | 3x+4y=2x+6 | | 1/4(2/9-2x)-5/9=4/9 | | 9m+4= | | g-3-7=15 | | 8+x=-17 | | 8+-25=-17 | | 36*130= | | 2x+27=2x-24 | | 1/6-7/3= | | X+2.4=2.7 | | 5r+4=4r+16 | | 6x-8/3=6x | | 2log(x-1)=4 | | 5x-6+x=90 | | 5+-4r=5-4r | | 8-5y=10 | | s=-36+44 | | 2cdot(x-3)=65 | | h(t)=-16t^2+vt+30 | | h(t)=-16t^2+30+s | | 70=s+24 | | h(30)=-16t^2+vt+s | | 10n^2=-3 | | 7=6n+1 | | 27x=6 | | -7x-6(-2x+3)=27 | | f(3)=6x+2 | | 3=-2g+11 |

Equations solver categories