(x*x)+7=9x

Simple and best practice solution for (x*x)+7=9x 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*x)+7=9x equation:


Simplifying
(x * x) + 7 = 9x

Multiply x * x
(x2) + 7 = 9x
x2 + 7 = 9x

Reorder the terms:
7 + x2 = 9x

Solving
7 + x2 = 9x

Solving for variable 'x'.

Reorder the terms:
7 + -9x + x2 = 9x + -9x

Combine like terms: 9x + -9x = 0
7 + -9x + x2 = 0

Begin completing the square.

Move the constant term to the right:

Add '-7' to each side of the equation.
7 + -9x + -7 + x2 = 0 + -7

Reorder the terms:
7 + -7 + -9x + x2 = 0 + -7

Combine like terms: 7 + -7 = 0
0 + -9x + x2 = 0 + -7
-9x + x2 = 0 + -7

Combine like terms: 0 + -7 = -7
-9x + x2 = -7

The x term is -9x.  Take half its coefficient (-4.5).
Square it (20.25) and add it to both sides.

Add '20.25' to each side of the equation.
-9x + 20.25 + x2 = -7 + 20.25

Reorder the terms:
20.25 + -9x + x2 = -7 + 20.25

Combine like terms: -7 + 20.25 = 13.25
20.25 + -9x + x2 = 13.25

Factor a perfect square on the left side:
(x + -4.5)(x + -4.5) = 13.25

Calculate the square root of the right side: 3.640054945

Break this problem into two subproblems by setting 
(x + -4.5) equal to 3.640054945 and -3.640054945.

Subproblem 1

x + -4.5 = 3.640054945 Simplifying x + -4.5 = 3.640054945 Reorder the terms: -4.5 + x = 3.640054945 Solving -4.5 + x = 3.640054945 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '4.5' to each side of the equation. -4.5 + 4.5 + x = 3.640054945 + 4.5 Combine like terms: -4.5 + 4.5 = 0.0 0.0 + x = 3.640054945 + 4.5 x = 3.640054945 + 4.5 Combine like terms: 3.640054945 + 4.5 = 8.140054945 x = 8.140054945 Simplifying x = 8.140054945

Subproblem 2

x + -4.5 = -3.640054945 Simplifying x + -4.5 = -3.640054945 Reorder the terms: -4.5 + x = -3.640054945 Solving -4.5 + x = -3.640054945 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '4.5' to each side of the equation. -4.5 + 4.5 + x = -3.640054945 + 4.5 Combine like terms: -4.5 + 4.5 = 0.0 0.0 + x = -3.640054945 + 4.5 x = -3.640054945 + 4.5 Combine like terms: -3.640054945 + 4.5 = 0.859945055 x = 0.859945055 Simplifying x = 0.859945055

Solution

The solution to the problem is based on the solutions from the subproblems. x = {8.140054945, 0.859945055}

See similar equations:

| a^2+6a=55 | | 2(5x+2)=-3(x-7) | | (t^2)+(5t)-1=0 | | 20y+4=8 | | (2y-3)2-2(y+1)2+7=0 | | -4x+2=-7x-5 | | 2y-9x=-90 | | (X+3)(x^2-3x+9)=0 | | y=x^4+3x^3-24x^2-80x | | 2x-9=-16 | | 2(2x+3)+8=4x+14 | | 4(3x-1)+13=12x+9 | | x^2+4x=70 | | 6x+9=6(x+4) | | 19-(-8)-(14)= | | 4(2x-1)-3(2-x)=12 | | 16-24+4=0 | | 7x+4(x+77)=0 | | 2(x+7)-9=5 | | F(x)=x^2+x+3 | | -3x+4y=-24 | | 18+b=a | | x^4-17x^2y^2+16y^4= | | 15x-2=35x+6 | | 52=7+3x | | 2(x+5)-8=6x-4(1+x) | | 10x^2(x-5)-11x(x-5)-8(x-5)= | | 52=7x+3x | | 9(552)=5f-160 | | (x-2)=3x-22 | | 27y^4-12y^2= | | 2ln(7x)=2 |

Equations solver categories