x^2-7=4x

Simple and best practice solution for x^2-7=4x 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^2-7=4x equation:


Simplifying
x2 + -7 = 4x

Reorder the terms:
-7 + x2 = 4x

Solving
-7 + x2 = 4x

Solving for variable 'x'.

Reorder the terms:
-7 + -4x + x2 = 4x + -4x

Combine like terms: 4x + -4x = 0
-7 + -4x + x2 = 0

Begin completing the square.

Move the constant term to the right:

Add '7' to each side of the equation.
-7 + -4x + 7 + x2 = 0 + 7

Reorder the terms:
-7 + 7 + -4x + x2 = 0 + 7

Combine like terms: -7 + 7 = 0
0 + -4x + x2 = 0 + 7
-4x + x2 = 0 + 7

Combine like terms: 0 + 7 = 7
-4x + x2 = 7

The x term is -4x.  Take half its coefficient (-2).
Square it (4) and add it to both sides.

Add '4' to each side of the equation.
-4x + 4 + x2 = 7 + 4

Reorder the terms:
4 + -4x + x2 = 7 + 4

Combine like terms: 7 + 4 = 11
4 + -4x + x2 = 11

Factor a perfect square on the left side:
(x + -2)(x + -2) = 11

Calculate the square root of the right side: 3.31662479

Break this problem into two subproblems by setting 
(x + -2) equal to 3.31662479 and -3.31662479.

Subproblem 1

x + -2 = 3.31662479 Simplifying x + -2 = 3.31662479 Reorder the terms: -2 + x = 3.31662479 Solving -2 + x = 3.31662479 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '2' to each side of the equation. -2 + 2 + x = 3.31662479 + 2 Combine like terms: -2 + 2 = 0 0 + x = 3.31662479 + 2 x = 3.31662479 + 2 Combine like terms: 3.31662479 + 2 = 5.31662479 x = 5.31662479 Simplifying x = 5.31662479

Subproblem 2

x + -2 = -3.31662479 Simplifying x + -2 = -3.31662479 Reorder the terms: -2 + x = -3.31662479 Solving -2 + x = -3.31662479 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '2' to each side of the equation. -2 + 2 + x = -3.31662479 + 2 Combine like terms: -2 + 2 = 0 0 + x = -3.31662479 + 2 x = -3.31662479 + 2 Combine like terms: -3.31662479 + 2 = -1.31662479 x = -1.31662479 Simplifying x = -1.31662479

Solution

The solution to the problem is based on the solutions from the subproblems. x = {5.31662479, -1.31662479}

See similar equations:

| n/6.4=2.4 | | 60x^3-8x^2-4x=0 | | 2z=8 | | 2(x+4)-5(x+3)=2 | | -7p=14 | | z-1=1 | | 2(3x-5)-4=2(x-3)+28 | | 8(a-10)=16 | | 24x=720 | | -3x=2x-10-5x | | -3x+7=-1 | | -5(x-1)=12 | | 2x+5+4x+11=40 | | (5x+6)(3x-8)=0 | | 2y-4=10y+28 | | 5x=360 | | 5x-5=3x+35 | | 8x-6=5x-75 | | 4=c+7 | | 15p+4=5p*4 | | n+8=-8 | | 6x+7=4x+49 | | (2x-30)+x=360 | | ax^2-20x+25=0 | | 16y^2=35 | | -2x-18=6(1-2x)+4x | | 9x-3=43 | | 16y^2-6=29 | | 9x+3=43 | | 2(x-6)=-8+4(x+2) | | 12x-7=5x | | 8r-1=15r-15 |

Equations solver categories