n^2-3n-20=0

Simple and best practice solution for n^2-3n-20=0 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 n^2-3n-20=0 equation:


Simplifying
n2 + -3n + -20 = 0

Reorder the terms:
-20 + -3n + n2 = 0

Solving
-20 + -3n + n2 = 0

Solving for variable 'n'.

Begin completing the square.

Move the constant term to the right:

Add '20' to each side of the equation.
-20 + -3n + 20 + n2 = 0 + 20

Reorder the terms:
-20 + 20 + -3n + n2 = 0 + 20

Combine like terms: -20 + 20 = 0
0 + -3n + n2 = 0 + 20
-3n + n2 = 0 + 20

Combine like terms: 0 + 20 = 20
-3n + n2 = 20

The n term is -3n.  Take half its coefficient (-1.5).
Square it (2.25) and add it to both sides.

Add '2.25' to each side of the equation.
-3n + 2.25 + n2 = 20 + 2.25

Reorder the terms:
2.25 + -3n + n2 = 20 + 2.25

Combine like terms: 20 + 2.25 = 22.25
2.25 + -3n + n2 = 22.25

Factor a perfect square on the left side:
(n + -1.5)(n + -1.5) = 22.25

Calculate the square root of the right side: 4.716990566

Break this problem into two subproblems by setting 
(n + -1.5) equal to 4.716990566 and -4.716990566.

Subproblem 1

n + -1.5 = 4.716990566 Simplifying n + -1.5 = 4.716990566 Reorder the terms: -1.5 + n = 4.716990566 Solving -1.5 + n = 4.716990566 Solving for variable 'n'. Move all terms containing n to the left, all other terms to the right. Add '1.5' to each side of the equation. -1.5 + 1.5 + n = 4.716990566 + 1.5 Combine like terms: -1.5 + 1.5 = 0.0 0.0 + n = 4.716990566 + 1.5 n = 4.716990566 + 1.5 Combine like terms: 4.716990566 + 1.5 = 6.216990566 n = 6.216990566 Simplifying n = 6.216990566

Subproblem 2

n + -1.5 = -4.716990566 Simplifying n + -1.5 = -4.716990566 Reorder the terms: -1.5 + n = -4.716990566 Solving -1.5 + n = -4.716990566 Solving for variable 'n'. Move all terms containing n to the left, all other terms to the right. Add '1.5' to each side of the equation. -1.5 + 1.5 + n = -4.716990566 + 1.5 Combine like terms: -1.5 + 1.5 = 0.0 0.0 + n = -4.716990566 + 1.5 n = -4.716990566 + 1.5 Combine like terms: -4.716990566 + 1.5 = -3.216990566 n = -3.216990566 Simplifying n = -3.216990566

Solution

The solution to the problem is based on the solutions from the subproblems. n = {6.216990566, -3.216990566}

See similar equations:

| 0.2(x+60)+0.2x=16 | | 34.77-26.98=5r | | -1/9(x-27)+1/3(x+3)=x-17 | | 6(x+1)=3(2x+6)-12 | | 7+7(5a+2)= | | 10(t-4)+8t=6(3t+3)-8 | | -(8y+5)-(-7y-6)=-4 | | 8+3(4a+2)= | | -2(4s-2)-4=-3(6s+5)-5 | | -2(3s-2)-4=-2(5s+4)-2 | | 2-4(9a-7)= | | 6x-x(3x+x-7)=3x(x+4) | | -2(4s-2)-4=-3(4s+2)-3 | | -2(4s-2)-4=3(4s+2)-3 | | 2x^3-14x^2+24=0 | | -4x-2y-4z=-10 | | 4a+6b-7a+4b= | | 0.2(10,000)-0.08y=0.02(y+10,000) | | 3x-4=2-5x | | 3x-4=2-,5x | | 6x+19=9x-14 | | 3(9x-2)=5(3x+7) | | 4(4x-2+3x)=2x(x- 5+3x) | | 36+-0.25y^2=0 | | m^2+3m-18=0 | | 36-025y^2=0 | | 0.19(10,000)-0.03y=0.07(y+10,000) | | 10(2m+1)=6(3m+4) | | 172-3x=33x+24 | | 0.50x+.05(8-x)=.10(-23) | | 5(2y-3)=2(3y+1) | | 0.54(18)+0.06x=0.18(24+x) |

Equations solver categories