7v^2+2v-21=0

Simple and best practice solution for 7v^2+2v-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 7v^2+2v-21=0 equation:


Simplifying
7v2 + 2v + -21 = 0

Reorder the terms:
-21 + 2v + 7v2 = 0

Solving
-21 + 2v + 7v2 = 0

Solving for variable 'v'.

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

Divide each side by '7'.
-3 + 0.2857142857v + v2 = 0

Move the constant term to the right:

Add '3' to each side of the equation.
-3 + 0.2857142857v + 3 + v2 = 0 + 3

Reorder the terms:
-3 + 3 + 0.2857142857v + v2 = 0 + 3

Combine like terms: -3 + 3 = 0
0 + 0.2857142857v + v2 = 0 + 3
0.2857142857v + v2 = 0 + 3

Combine like terms: 0 + 3 = 3
0.2857142857v + v2 = 3

The v term is 0.2857142857v.  Take half its coefficient (0.1428571429).
Square it (0.02040816328) and add it to both sides.

Add '0.02040816328' to each side of the equation.
0.2857142857v + 0.02040816328 + v2 = 3 + 0.02040816328

Reorder the terms:
0.02040816328 + 0.2857142857v + v2 = 3 + 0.02040816328

Combine like terms: 3 + 0.02040816328 = 3.02040816328
0.02040816328 + 0.2857142857v + v2 = 3.02040816328

Factor a perfect square on the left side:
(v + 0.1428571429)(v + 0.1428571429) = 3.02040816328

Calculate the square root of the right side: 1.737932152

Break this problem into two subproblems by setting 
(v + 0.1428571429) equal to 1.737932152 and -1.737932152.

Subproblem 1

v + 0.1428571429 = 1.737932152 Simplifying v + 0.1428571429 = 1.737932152 Reorder the terms: 0.1428571429 + v = 1.737932152 Solving 0.1428571429 + v = 1.737932152 Solving for variable 'v'. Move all terms containing v to the left, all other terms to the right. Add '-0.1428571429' to each side of the equation. 0.1428571429 + -0.1428571429 + v = 1.737932152 + -0.1428571429 Combine like terms: 0.1428571429 + -0.1428571429 = 0.0000000000 0.0000000000 + v = 1.737932152 + -0.1428571429 v = 1.737932152 + -0.1428571429 Combine like terms: 1.737932152 + -0.1428571429 = 1.5950750091 v = 1.5950750091 Simplifying v = 1.5950750091

Subproblem 2

v + 0.1428571429 = -1.737932152 Simplifying v + 0.1428571429 = -1.737932152 Reorder the terms: 0.1428571429 + v = -1.737932152 Solving 0.1428571429 + v = -1.737932152 Solving for variable 'v'. Move all terms containing v to the left, all other terms to the right. Add '-0.1428571429' to each side of the equation. 0.1428571429 + -0.1428571429 + v = -1.737932152 + -0.1428571429 Combine like terms: 0.1428571429 + -0.1428571429 = 0.0000000000 0.0000000000 + v = -1.737932152 + -0.1428571429 v = -1.737932152 + -0.1428571429 Combine like terms: -1.737932152 + -0.1428571429 = -1.8807892949 v = -1.8807892949 Simplifying v = -1.8807892949

Solution

The solution to the problem is based on the solutions from the subproblems. v = {1.5950750091, -1.8807892949}

See similar equations:

| 0.20x+0.05(14-x)=0.10(34) | | (2x+5y+3)(-xy)= | | 3-2y=-2 | | 8-6(7-4t)+4t= | | 2(x+4)(3x-1)=0 | | c^3+125= | | X-3/x^2-4 | | 3(x+1)=2-(4-x) | | 2.5x-2.9y+5.3x-0.3y= | | 7n+8=8n-5 | | (x^2-3x+2)(2x-4)=x | | 62.8*4.6= | | 0=6x^2-x-2 | | h(t)=16t^2+5776 | | sin(6x)-cos(2x)=0 | | 3(6s+6)-14s=2(2s+6)-15 | | b/-12-8=-6 | | 5(x+3)+6=4x+3 | | 3(8s+4)-12s=3(4s+3)-12 | | 180=123+(x-3) | | 3(8x+4)-12s=3(4s+3)-12 | | 5*-4=8 | | 5x^2+4x+16=0 | | 5*-4=-8 | | 2y+6=-5 | | 19-4x=133 | | 4(2x-1)+3=71 | | 8x^2+8x+10=8 | | 2(5x+3)-4(x+1)=88 | | 3(x+1)=2x-(4-1) | | 2(4x+16)=-5(2x+4) | | 9j-(5j+1)-[2+8j-(7j-5)]+9j=0 |

Equations solver categories