4x^2-9x=18

Simple and best practice solution for 4x^2-9x=18 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 4x^2-9x=18 equation:


Simplifying
4x2 + -9x = 18

Reorder the terms:
-9x + 4x2 = 18

Solving
-9x + 4x2 = 18

Solving for variable 'x'.

Reorder the terms:
-18 + -9x + 4x2 = 18 + -18

Combine like terms: 18 + -18 = 0
-18 + -9x + 4x2 = 0

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

Divide each side by '4'.
-4.5 + -2.25x + x2 = 0

Move the constant term to the right:

Add '4.5' to each side of the equation.
-4.5 + -2.25x + 4.5 + x2 = 0 + 4.5

Reorder the terms:
-4.5 + 4.5 + -2.25x + x2 = 0 + 4.5

Combine like terms: -4.5 + 4.5 = 0.0
0.0 + -2.25x + x2 = 0 + 4.5
-2.25x + x2 = 0 + 4.5

Combine like terms: 0 + 4.5 = 4.5
-2.25x + x2 = 4.5

The x term is -2.25x.  Take half its coefficient (-1.125).
Square it (1.265625) and add it to both sides.

Add '1.265625' to each side of the equation.
-2.25x + 1.265625 + x2 = 4.5 + 1.265625

Reorder the terms:
1.265625 + -2.25x + x2 = 4.5 + 1.265625

Combine like terms: 4.5 + 1.265625 = 5.765625
1.265625 + -2.25x + x2 = 5.765625

Factor a perfect square on the left side:
(x + -1.125)(x + -1.125) = 5.765625

Calculate the square root of the right side: 2.401171589

Break this problem into two subproblems by setting 
(x + -1.125) equal to 2.401171589 and -2.401171589.

Subproblem 1

x + -1.125 = 2.401171589 Simplifying x + -1.125 = 2.401171589 Reorder the terms: -1.125 + x = 2.401171589 Solving -1.125 + x = 2.401171589 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '1.125' to each side of the equation. -1.125 + 1.125 + x = 2.401171589 + 1.125 Combine like terms: -1.125 + 1.125 = 0.000 0.000 + x = 2.401171589 + 1.125 x = 2.401171589 + 1.125 Combine like terms: 2.401171589 + 1.125 = 3.526171589 x = 3.526171589 Simplifying x = 3.526171589

Subproblem 2

x + -1.125 = -2.401171589 Simplifying x + -1.125 = -2.401171589 Reorder the terms: -1.125 + x = -2.401171589 Solving -1.125 + x = -2.401171589 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '1.125' to each side of the equation. -1.125 + 1.125 + x = -2.401171589 + 1.125 Combine like terms: -1.125 + 1.125 = 0.000 0.000 + x = -2.401171589 + 1.125 x = -2.401171589 + 1.125 Combine like terms: -2.401171589 + 1.125 = -1.276171589 x = -1.276171589 Simplifying x = -1.276171589

Solution

The solution to the problem is based on the solutions from the subproblems. x = {3.526171589, -1.276171589}

See similar equations:

| 4+24x=9x^2 | | 28+1x=12 | | -2a+27+8a=3a-6a | | x^2+1=6x | | y=2(-2)+12 | | L=7*3.14zx+3*3.14z^2 | | 9(x-5(6-x))= | | 3x(x-8)=0 | | 40=-5p | | 12x+30=5x | | 2b+3a=21 | | 9n-(7-6n)= | | z-9z=5z-1-z | | x^2-4x+29=0 | | 5c+8-4c-2-c= | | (2x-5)(x+1)=2 | | 2x-y= | | 8x^2+9=18x | | 5t^2-11t-12=0 | | -(6xy-11)+2(5xy+7)= | | 3-6a-8-2a= | | 45x^2+19x=42 | | 0=8x^2+5x | | 8+(-3)+(-15)+4= | | 15+20x=90-3x | | 24x^2+13x=7 | | 5x+3=7x+2 | | 5(4x-1)-20x= | | 28y^2+25y+3= | | 42x^2-40=13x | | 5x-2z=90 | | -4+12=14x-2-13x |

Equations solver categories