7x-x^2=8

Simple and best practice solution for 7x-x^2=8 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 7x-x^2=8 equation:


Simplifying
7x + -1x2 = 8

Solving
7x + -1x2 = 8

Solving for variable 'x'.

Reorder the terms:
-8 + 7x + -1x2 = 8 + -8

Combine like terms: 8 + -8 = 0
-8 + 7x + -1x2 = 0

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

Divide each side by '-1'.
8 + -7x + x2 = 0

Move the constant term to the right:

Add '-8' to each side of the equation.
8 + -7x + -8 + x2 = 0 + -8

Reorder the terms:
8 + -8 + -7x + x2 = 0 + -8

Combine like terms: 8 + -8 = 0
0 + -7x + x2 = 0 + -8
-7x + x2 = 0 + -8

Combine like terms: 0 + -8 = -8
-7x + x2 = -8

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 = -8 + 12.25

Reorder the terms:
12.25 + -7x + x2 = -8 + 12.25

Combine like terms: -8 + 12.25 = 4.25
12.25 + -7x + x2 = 4.25

Factor a perfect square on the left side:
(x + -3.5)(x + -3.5) = 4.25

Calculate the square root of the right side: 2.061552813

Break this problem into two subproblems by setting 
(x + -3.5) equal to 2.061552813 and -2.061552813.

Subproblem 1

x + -3.5 = 2.061552813 Simplifying x + -3.5 = 2.061552813 Reorder the terms: -3.5 + x = 2.061552813 Solving -3.5 + x = 2.061552813 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 = 2.061552813 + 3.5 Combine like terms: -3.5 + 3.5 = 0.0 0.0 + x = 2.061552813 + 3.5 x = 2.061552813 + 3.5 Combine like terms: 2.061552813 + 3.5 = 5.561552813 x = 5.561552813 Simplifying x = 5.561552813

Subproblem 2

x + -3.5 = -2.061552813 Simplifying x + -3.5 = -2.061552813 Reorder the terms: -3.5 + x = -2.061552813 Solving -3.5 + x = -2.061552813 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 = -2.061552813 + 3.5 Combine like terms: -3.5 + 3.5 = 0.0 0.0 + x = -2.061552813 + 3.5 x = -2.061552813 + 3.5 Combine like terms: -2.061552813 + 3.5 = 1.438447187 x = 1.438447187 Simplifying x = 1.438447187

Solution

The solution to the problem is based on the solutions from the subproblems. x = {5.561552813, 1.438447187}

See similar equations:

| y=0.7x+0.1 | | 5(2x+7)=-33+48 | | Log(2x+5)=-0.6 | | 14+2x=77 | | 39x+65y= | | 14*2x=77 | | 120+x=250 | | 25X+14Y=7 | | -2x+0x+7+5x=30+40 | | y-6=1/2(x-(3) | | 3x-3-2(2x+1)=-5 | | 7p-6(p-7)+(q-7)= | | (8-y)(2y-7)=0 | | y^3-12y^2+27=0 | | 2u-6+2(5u+7)=-2(u+1) | | x^2+3x-8x-16=10 | | 2(2x+5)-(3x-6)=4 | | 3(m+5)=2(m+4m-4) | | 3D(d-2)=0 | | 4(u+6)=-2(5u-8)+8u | | 0.27v-1.6=0.36v-2 | | 3x-5=6-7x | | 2x-3x=8x | | 7p-6(p-7)+2(q-7)= | | 6(u-4)-1=-5(-5u+6)-4u | | y=senx-2 | | 1.5x+y=1.2 | | f(x)=5+6x^2+7x | | 32^6x/8^-10x | | f(x)=5+6x^2-7x | | F(x)=2*(.5)x | | 2x+27=0 |

Equations solver categories