2x^2-7x-18=0

Simple and best practice solution for 2x^2-7x-18=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^2-7x-18=0 equation:


Simplifying
2x2 + -7x + -18 = 0

Reorder the terms:
-18 + -7x + 2x2 = 0

Solving
-18 + -7x + 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'.
-9 + -3.5x + x2 = 0

Move the constant term to the right:

Add '9' to each side of the equation.
-9 + -3.5x + 9 + x2 = 0 + 9

Reorder the terms:
-9 + 9 + -3.5x + x2 = 0 + 9

Combine like terms: -9 + 9 = 0
0 + -3.5x + x2 = 0 + 9
-3.5x + x2 = 0 + 9

Combine like terms: 0 + 9 = 9
-3.5x + x2 = 9

The x term is -3.5x.  Take half its coefficient (-1.75).
Square it (3.0625) and add it to both sides.

Add '3.0625' to each side of the equation.
-3.5x + 3.0625 + x2 = 9 + 3.0625

Reorder the terms:
3.0625 + -3.5x + x2 = 9 + 3.0625

Combine like terms: 9 + 3.0625 = 12.0625
3.0625 + -3.5x + x2 = 12.0625

Factor a perfect square on the left side:
(x + -1.75)(x + -1.75) = 12.0625

Calculate the square root of the right side: 3.473110997

Break this problem into two subproblems by setting 
(x + -1.75) equal to 3.473110997 and -3.473110997.

Subproblem 1

x + -1.75 = 3.473110997 Simplifying x + -1.75 = 3.473110997 Reorder the terms: -1.75 + x = 3.473110997 Solving -1.75 + x = 3.473110997 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '1.75' to each side of the equation. -1.75 + 1.75 + x = 3.473110997 + 1.75 Combine like terms: -1.75 + 1.75 = 0.00 0.00 + x = 3.473110997 + 1.75 x = 3.473110997 + 1.75 Combine like terms: 3.473110997 + 1.75 = 5.223110997 x = 5.223110997 Simplifying x = 5.223110997

Subproblem 2

x + -1.75 = -3.473110997 Simplifying x + -1.75 = -3.473110997 Reorder the terms: -1.75 + x = -3.473110997 Solving -1.75 + x = -3.473110997 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '1.75' to each side of the equation. -1.75 + 1.75 + x = -3.473110997 + 1.75 Combine like terms: -1.75 + 1.75 = 0.00 0.00 + x = -3.473110997 + 1.75 x = -3.473110997 + 1.75 Combine like terms: -3.473110997 + 1.75 = -1.723110997 x = -1.723110997 Simplifying x = -1.723110997

Solution

The solution to the problem is based on the solutions from the subproblems. x = {5.223110997, -1.723110997}

See similar equations:

| 2(4+3x)=38 | | 3-2z/9=7-2z/3 | | 3(2x+5)=69 | | 50(14.50)=15n+5 | | 2(6x+5)=10 | | 20(14.10)=25n+7 | | 7(2x+1)=91 | | 0.5x+0.6x+8=x | | 4.24-2.14x=3x-2.699 | | -5(3y-8)+2(2y+8)= | | 6(5+3x)=48 | | 4a-7=5 | | 4x+3/7+1=7x+1/2-2 | | 4x+10=5x+8 | | a/4+4/8=8a/7+7/3 | | 4.7-2.5+2.7x=12.8-1.6x | | 2+5y/8=2/8+5y | | 11=2b | | -9z-2z=2z-1+7z | | 4-3z/5=7-3z/4 | | 4+6x=2x+16 | | 10-3x-6-7x=6 | | 2.5-x=2+1.5x | | (3v-4)(4v-6)= | | x+2=-10+3x | | -4(4y+5)-11=-8(y+5)+4y | | -9(v+2)+3v+7=8v+6 | | 5x+4=4x+12 | | 9+4(x-2)=6x | | 2(2x+2)=3(x-3) | | -3(5-4k)=6k+15 | | -2x-5(x+6)=-2(3x+9) |

Equations solver categories