81+30x-x^2=0

Simple and best practice solution for 81+30x-x^2=0 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 81+30x-x^2=0 equation:


Simplifying
81 + 30x + -1x2 = 0

Solving
81 + 30x + -1x2 = 0

Solving for variable 'x'.

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

Divide each side by '-1'.
-81 + -30x + x2 = 0

Move the constant term to the right:

Add '81' to each side of the equation.
-81 + -30x + 81 + x2 = 0 + 81

Reorder the terms:
-81 + 81 + -30x + x2 = 0 + 81

Combine like terms: -81 + 81 = 0
0 + -30x + x2 = 0 + 81
-30x + x2 = 0 + 81

Combine like terms: 0 + 81 = 81
-30x + x2 = 81

The x term is -30x.  Take half its coefficient (-15).
Square it (225) and add it to both sides.

Add '225' to each side of the equation.
-30x + 225 + x2 = 81 + 225

Reorder the terms:
225 + -30x + x2 = 81 + 225

Combine like terms: 81 + 225 = 306
225 + -30x + x2 = 306

Factor a perfect square on the left side:
(x + -15)(x + -15) = 306

Calculate the square root of the right side: 17.492855685

Break this problem into two subproblems by setting 
(x + -15) equal to 17.492855685 and -17.492855685.

Subproblem 1

x + -15 = 17.492855685 Simplifying x + -15 = 17.492855685 Reorder the terms: -15 + x = 17.492855685 Solving -15 + x = 17.492855685 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '15' to each side of the equation. -15 + 15 + x = 17.492855685 + 15 Combine like terms: -15 + 15 = 0 0 + x = 17.492855685 + 15 x = 17.492855685 + 15 Combine like terms: 17.492855685 + 15 = 32.492855685 x = 32.492855685 Simplifying x = 32.492855685

Subproblem 2

x + -15 = -17.492855685 Simplifying x + -15 = -17.492855685 Reorder the terms: -15 + x = -17.492855685 Solving -15 + x = -17.492855685 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '15' to each side of the equation. -15 + 15 + x = -17.492855685 + 15 Combine like terms: -15 + 15 = 0 0 + x = -17.492855685 + 15 x = -17.492855685 + 15 Combine like terms: -17.492855685 + 15 = -2.492855685 x = -2.492855685 Simplifying x = -2.492855685

Solution

The solution to the problem is based on the solutions from the subproblems. x = {32.492855685, -2.492855685}

See similar equations:

| -18-2=5x+13 | | x^2-30x-81=0 | | 136/1*11/34*9/16 | | 2c-2l=0 | | 8p+6q=54 | | 59999-60000= | | 4x^2-15+9=-3x+4 | | 2(a-4)=4a+(2a+4) | | 4x+x+(x-10)=188 | | 5x-.6=2x | | 15=3xn-21 | | 20w-w^2-91=0 | | 136*11/34*9/16 | | 2x+(3x+4)=(x-2) | | 5(n+3)=45 | | 5(3x-2)=2(3x-2) | | (3x-4)= | | 11m+13=m+3 | | 4x^2-15x+11=5x+2 | | 1.3x-1.2(x-1.5)=1.5 | | 0.4(3y-8)=-(6-4y) | | 0.34x+2.82=3-0.38x | | 22+22+x=y | | 5.27-7.77/5.27 | | -8+6b-4b=5b-2 | | 0.25x+0.5x=1 | | 4x+2-2x=52 | | 6x+11-4x=-5x-10+x | | 25x^2+10x= | | 5-2x+-4=6 | | -2.3x+1.33=1.67-3.05x | | 30x-11=30/x |

Equations solver categories