k^2+7k-1=9

Simple and best practice solution for k^2+7k-1=9 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 k^2+7k-1=9 equation:


Simplifying
k2 + 7k + -1 = 9

Reorder the terms:
-1 + 7k + k2 = 9

Solving
-1 + 7k + k2 = 9

Solving for variable 'k'.

Reorder the terms:
-1 + -9 + 7k + k2 = 9 + -9

Combine like terms: -1 + -9 = -10
-10 + 7k + k2 = 9 + -9

Combine like terms: 9 + -9 = 0
-10 + 7k + k2 = 0

Begin completing the square.

Move the constant term to the right:

Add '10' to each side of the equation.
-10 + 7k + 10 + k2 = 0 + 10

Reorder the terms:
-10 + 10 + 7k + k2 = 0 + 10

Combine like terms: -10 + 10 = 0
0 + 7k + k2 = 0 + 10
7k + k2 = 0 + 10

Combine like terms: 0 + 10 = 10
7k + k2 = 10

The k term is 7k.  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.
7k + 12.25 + k2 = 10 + 12.25

Reorder the terms:
12.25 + 7k + k2 = 10 + 12.25

Combine like terms: 10 + 12.25 = 22.25
12.25 + 7k + k2 = 22.25

Factor a perfect square on the left side:
(k + 3.5)(k + 3.5) = 22.25

Calculate the square root of the right side: 4.716990566

Break this problem into two subproblems by setting 
(k + 3.5) equal to 4.716990566 and -4.716990566.

Subproblem 1

k + 3.5 = 4.716990566 Simplifying k + 3.5 = 4.716990566 Reorder the terms: 3.5 + k = 4.716990566 Solving 3.5 + k = 4.716990566 Solving for variable 'k'. Move all terms containing k to the left, all other terms to the right. Add '-3.5' to each side of the equation. 3.5 + -3.5 + k = 4.716990566 + -3.5 Combine like terms: 3.5 + -3.5 = 0.0 0.0 + k = 4.716990566 + -3.5 k = 4.716990566 + -3.5 Combine like terms: 4.716990566 + -3.5 = 1.216990566 k = 1.216990566 Simplifying k = 1.216990566

Subproblem 2

k + 3.5 = -4.716990566 Simplifying k + 3.5 = -4.716990566 Reorder the terms: 3.5 + k = -4.716990566 Solving 3.5 + k = -4.716990566 Solving for variable 'k'. Move all terms containing k to the left, all other terms to the right. Add '-3.5' to each side of the equation. 3.5 + -3.5 + k = -4.716990566 + -3.5 Combine like terms: 3.5 + -3.5 = 0.0 0.0 + k = -4.716990566 + -3.5 k = -4.716990566 + -3.5 Combine like terms: -4.716990566 + -3.5 = -8.216990566 k = -8.216990566 Simplifying k = -8.216990566

Solution

The solution to the problem is based on the solutions from the subproblems. k = {1.216990566, -8.216990566}

See similar equations:

| (-15c)+(-c)+17c+5c-(-14)=(-16) | | n^2=-3n+40 | | 56-(2c+4)=4(c+6)+c | | 5m^2-3m-14=0 | | z/4+8=9-z/4 | | 8j-5j-j+2j-3=9 | | 25x^2+10x+1=16 | | Y=-5x^2+20x-14 | | 13b-11b+3b+3=13 | | 7=63/n | | 7x-5=y | | 13g+(-10g)+16g-18g=(-8) | | b^2+12b-64=0 | | 6xc=576 | | 2/3x+6=-12 | | 3=(x*1.10)+((x+.65)*1.25) | | 8x+10y=-8 | | 8j*2-4j-18=0 | | 9xc=855 | | 2x^(1/3)-2=0 | | 15y-10y=25 | | 3=(x*1.10)+(x+.65) | | 141+2h=991 | | x^(1/2)-5=0 | | 3h/7-4=629/42 | | 49x^2+1=82 | | 13y-10y-8=35.68 | | -4y^2-7y=1 | | 4(x-5)-5=6x | | 875=5(x+17) | | x^2+57-44=0 | | 4x-9=7x+2 |

Equations solver categories