2x^2-11x-84=0

Simple and best practice solution for 2x^2-11x-84=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 2x^2-11x-84=0 equation:


Simplifying
2x2 + -11x + -84 = 0

Reorder the terms:
-84 + -11x + 2x2 = 0

Solving
-84 + -11x + 2x2 = 0

Solving for variable 'x'.

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

Divide each side by '2'.
-42 + -5.5x + x2 = 0

Move the constant term to the right:

Add '42' to each side of the equation.
-42 + -5.5x + 42 + x2 = 0 + 42

Reorder the terms:
-42 + 42 + -5.5x + x2 = 0 + 42

Combine like terms: -42 + 42 = 0
0 + -5.5x + x2 = 0 + 42
-5.5x + x2 = 0 + 42

Combine like terms: 0 + 42 = 42
-5.5x + x2 = 42

The x term is -5.5x.  Take half its coefficient (-2.75).
Square it (7.5625) and add it to both sides.

Add '7.5625' to each side of the equation.
-5.5x + 7.5625 + x2 = 42 + 7.5625

Reorder the terms:
7.5625 + -5.5x + x2 = 42 + 7.5625

Combine like terms: 42 + 7.5625 = 49.5625
7.5625 + -5.5x + x2 = 49.5625

Factor a perfect square on the left side:
(x + -2.75)(x + -2.75) = 49.5625

Calculate the square root of the right side: 7.04006392

Break this problem into two subproblems by setting 
(x + -2.75) equal to 7.04006392 and -7.04006392.

Subproblem 1

x + -2.75 = 7.04006392 Simplifying x + -2.75 = 7.04006392 Reorder the terms: -2.75 + x = 7.04006392 Solving -2.75 + x = 7.04006392 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '2.75' to each side of the equation. -2.75 + 2.75 + x = 7.04006392 + 2.75 Combine like terms: -2.75 + 2.75 = 0.00 0.00 + x = 7.04006392 + 2.75 x = 7.04006392 + 2.75 Combine like terms: 7.04006392 + 2.75 = 9.79006392 x = 9.79006392 Simplifying x = 9.79006392

Subproblem 2

x + -2.75 = -7.04006392 Simplifying x + -2.75 = -7.04006392 Reorder the terms: -2.75 + x = -7.04006392 Solving -2.75 + x = -7.04006392 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '2.75' to each side of the equation. -2.75 + 2.75 + x = -7.04006392 + 2.75 Combine like terms: -2.75 + 2.75 = 0.00 0.00 + x = -7.04006392 + 2.75 x = -7.04006392 + 2.75 Combine like terms: -7.04006392 + 2.75 = -4.29006392 x = -4.29006392 Simplifying x = -4.29006392

Solution

The solution to the problem is based on the solutions from the subproblems. x = {9.79006392, -4.29006392}

See similar equations:

| -16x^4-32x^3-80x^3=0 | | -3x+m=2x+p | | y=6y-24 | | y+2=3y | | 6-(-3)= | | 0=4x+5 | | m-3x=2x+p | | -7w=-49 | | 2(w+5)(w-2)=112 | | x+3x+2=102 | | -4x+7(1+3x)=3x+7 | | 15=12+6x | | 4-7w=-80 | | 60-3x=x | | 5x+10=8x-23 | | 7p+8=9p-9 | | -2x=4x-9 | | 4x=52-x-7 | | 2(x-5)=6(x+7) | | 7x+8=40-3x | | a+6x=c | | 7x+3-2x=23 | | 5n+7=7(n+3)-3n | | 2-(-5)= | | 7x^2+14x=-7 | | .5(5x+1)=4(2-3x)+7 | | (3x-2)(2x-1)=0 | | x^3+3x^2+25x+75=0 | | 6(5r-6)+8r=7-5r | | 4x^2+24x=-36 | | 10m=200 | | 2y+7(5)=4 |

Equations solver categories