3m^2+17m+21=0

Simple and best practice solution for 3m^2+17m+21=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 3m^2+17m+21=0 equation:


Simplifying
3m2 + 17m + 21 = 0

Reorder the terms:
21 + 17m + 3m2 = 0

Solving
21 + 17m + 3m2 = 0

Solving for variable 'm'.

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

Divide each side by '3'.
7 + 5.666666667m + m2 = 0

Move the constant term to the right:

Add '-7' to each side of the equation.
7 + 5.666666667m + -7 + m2 = 0 + -7

Reorder the terms:
7 + -7 + 5.666666667m + m2 = 0 + -7

Combine like terms: 7 + -7 = 0
0 + 5.666666667m + m2 = 0 + -7
5.666666667m + m2 = 0 + -7

Combine like terms: 0 + -7 = -7
5.666666667m + m2 = -7

The m term is 5.666666667m.  Take half its coefficient (2.833333334).
Square it (8.027777782) and add it to both sides.

Add '8.027777782' to each side of the equation.
5.666666667m + 8.027777782 + m2 = -7 + 8.027777782

Reorder the terms:
8.027777782 + 5.666666667m + m2 = -7 + 8.027777782

Combine like terms: -7 + 8.027777782 = 1.027777782
8.027777782 + 5.666666667m + m2 = 1.027777782

Factor a perfect square on the left side:
(m + 2.833333334)(m + 2.833333334) = 1.027777782

Calculate the square root of the right side: 1.013793757

Break this problem into two subproblems by setting 
(m + 2.833333334) equal to 1.013793757 and -1.013793757.

Subproblem 1

m + 2.833333334 = 1.013793757 Simplifying m + 2.833333334 = 1.013793757 Reorder the terms: 2.833333334 + m = 1.013793757 Solving 2.833333334 + m = 1.013793757 Solving for variable 'm'. Move all terms containing m to the left, all other terms to the right. Add '-2.833333334' to each side of the equation. 2.833333334 + -2.833333334 + m = 1.013793757 + -2.833333334 Combine like terms: 2.833333334 + -2.833333334 = 0.000000000 0.000000000 + m = 1.013793757 + -2.833333334 m = 1.013793757 + -2.833333334 Combine like terms: 1.013793757 + -2.833333334 = -1.819539577 m = -1.819539577 Simplifying m = -1.819539577

Subproblem 2

m + 2.833333334 = -1.013793757 Simplifying m + 2.833333334 = -1.013793757 Reorder the terms: 2.833333334 + m = -1.013793757 Solving 2.833333334 + m = -1.013793757 Solving for variable 'm'. Move all terms containing m to the left, all other terms to the right. Add '-2.833333334' to each side of the equation. 2.833333334 + -2.833333334 + m = -1.013793757 + -2.833333334 Combine like terms: 2.833333334 + -2.833333334 = 0.000000000 0.000000000 + m = -1.013793757 + -2.833333334 m = -1.013793757 + -2.833333334 Combine like terms: -1.013793757 + -2.833333334 = -3.847127091 m = -3.847127091 Simplifying m = -3.847127091

Solution

The solution to the problem is based on the solutions from the subproblems. m = {-1.819539577, -3.847127091}

See similar equations:

| 2x^2+5x-720=0 | | x+x+5853=14165 | | 0.3x-2.1=0.3 | | 2*x+2*x=22 | | 0.10x+0.35(50)=24.5 | | 7x^4+3x^2=594 | | 7(r+6)=5(r+8) | | 2(6x-8)=1(16x-12) | | 16*7= | | 7t^2-46t-21=0 | | 3(x-2)=4-6x | | k+6=13 | | x+x-15=83 | | p^3+6p=5p^2 | | 4x-2x=200 | | 4x^2-2x=200 | | 7y^2-y+1=0 | | g=x+2 | | 8x+15=9x+10 | | 2b^2-7=13b | | 65-9x=11x | | 6-9x=11x | | (x-3)(5x+1)=0 | | -15x-5x=-4 | | -5r+4=9+3r+3r | | c^2-18c+81=0 | | -5r-4=9+3r+3r | | -3=-15-5x | | x-0.8x=116 | | 3c+2=c+6 | | -2=-9-3x | | 5x^2-13x=0 |

Equations solver categories