x^2-7x=40

Simple and best practice solution for x^2-7x=40 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^2-7x=40 equation:


Simplifying
x2 + -7x = 40

Reorder the terms:
-7x + x2 = 40

Solving
-7x + x2 = 40

Solving for variable 'x'.

Reorder the terms:
-40 + -7x + x2 = 40 + -40

Combine like terms: 40 + -40 = 0
-40 + -7x + x2 = 0

Begin completing the square.

Move the constant term to the right:

Add '40' to each side of the equation.
-40 + -7x + 40 + x2 = 0 + 40

Reorder the terms:
-40 + 40 + -7x + x2 = 0 + 40

Combine like terms: -40 + 40 = 0
0 + -7x + x2 = 0 + 40
-7x + x2 = 0 + 40

Combine like terms: 0 + 40 = 40
-7x + x2 = 40

The x term is -7x.  Take half its coefficient (-3.5).
Square it (12.25) and add it to both sides.

Add '12.25' to each side of the equation.
-7x + 12.25 + x2 = 40 + 12.25

Reorder the terms:
12.25 + -7x + x2 = 40 + 12.25

Combine like terms: 40 + 12.25 = 52.25
12.25 + -7x + x2 = 52.25

Factor a perfect square on the left side:
(x + -3.5)(x + -3.5) = 52.25

Calculate the square root of the right side: 7.228416147

Break this problem into two subproblems by setting 
(x + -3.5) equal to 7.228416147 and -7.228416147.

Subproblem 1

x + -3.5 = 7.228416147 Simplifying x + -3.5 = 7.228416147 Reorder the terms: -3.5 + x = 7.228416147 Solving -3.5 + x = 7.228416147 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '3.5' to each side of the equation. -3.5 + 3.5 + x = 7.228416147 + 3.5 Combine like terms: -3.5 + 3.5 = 0.0 0.0 + x = 7.228416147 + 3.5 x = 7.228416147 + 3.5 Combine like terms: 7.228416147 + 3.5 = 10.728416147 x = 10.728416147 Simplifying x = 10.728416147

Subproblem 2

x + -3.5 = -7.228416147 Simplifying x + -3.5 = -7.228416147 Reorder the terms: -3.5 + x = -7.228416147 Solving -3.5 + x = -7.228416147 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '3.5' to each side of the equation. -3.5 + 3.5 + x = -7.228416147 + 3.5 Combine like terms: -3.5 + 3.5 = 0.0 0.0 + x = -7.228416147 + 3.5 x = -7.228416147 + 3.5 Combine like terms: -7.228416147 + 3.5 = -3.728416147 x = -3.728416147 Simplifying x = -3.728416147

Solution

The solution to the problem is based on the solutions from the subproblems. x = {10.728416147, -3.728416147}

See similar equations:

| -5x+3=-6y+1 | | (x+1)(x+1)+3(x-4)=x(x-1)+1 | | 9p+9=17+8p | | 2x^3+3x^2+x+15= | | (x+1)(x+1)+3(x+4)=x(x-1)+1 | | Kx^2-3x+(k+2)=0 | | -8=-n-4 | | 24+k=-14 | | 2+5x=0 | | graphx=-6 | | 3x+18=192 | | 13n-2n= | | -5b+2b=-2-2(1-b) | | 6=14 | | 2(k-5)=3(1-2k) | | 6(4x)=46 | | 3(2x+5)=4(x+3) | | 2x-1x/2=3 | | y=3(2) | | 21y-14-7=0 | | 5t+7-3t+13=2(11+t) | | -2x+3+1=-7 | | 2x+14=15x-4 | | e^9x=2 | | 3x-(-4)=13 | | 25*2=b*2+24*2 | | 9m-12m= | | 7n=168 | | 40h+12(2h)=544 | | y+4=-6 | | y-3=2(x-1) | | -2(8-x)+3(x-8)=-1 |

Equations solver categories