2x^2-4x=15

Simple and best practice solution for 2x^2-4x=15 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^2-4x=15 equation:


Simplifying
2x2 + -4x = 15

Reorder the terms:
-4x + 2x2 = 15

Solving
-4x + 2x2 = 15

Solving for variable 'x'.

Reorder the terms:
-15 + -4x + 2x2 = 15 + -15

Combine like terms: 15 + -15 = 0
-15 + -4x + 2x2 = 0

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

Divide each side by '2'.
-7.5 + -2x + x2 = 0

Move the constant term to the right:

Add '7.5' to each side of the equation.
-7.5 + -2x + 7.5 + x2 = 0 + 7.5

Reorder the terms:
-7.5 + 7.5 + -2x + x2 = 0 + 7.5

Combine like terms: -7.5 + 7.5 = 0.0
0.0 + -2x + x2 = 0 + 7.5
-2x + x2 = 0 + 7.5

Combine like terms: 0 + 7.5 = 7.5
-2x + x2 = 7.5

The x term is -2x.  Take half its coefficient (-1).
Square it (1) and add it to both sides.

Add '1' to each side of the equation.
-2x + 1 + x2 = 7.5 + 1

Reorder the terms:
1 + -2x + x2 = 7.5 + 1

Combine like terms: 7.5 + 1 = 8.5
1 + -2x + x2 = 8.5

Factor a perfect square on the left side:
(x + -1)(x + -1) = 8.5

Calculate the square root of the right side: 2.915475947

Break this problem into two subproblems by setting 
(x + -1) equal to 2.915475947 and -2.915475947.

Subproblem 1

x + -1 = 2.915475947 Simplifying x + -1 = 2.915475947 Reorder the terms: -1 + x = 2.915475947 Solving -1 + x = 2.915475947 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '1' to each side of the equation. -1 + 1 + x = 2.915475947 + 1 Combine like terms: -1 + 1 = 0 0 + x = 2.915475947 + 1 x = 2.915475947 + 1 Combine like terms: 2.915475947 + 1 = 3.915475947 x = 3.915475947 Simplifying x = 3.915475947

Subproblem 2

x + -1 = -2.915475947 Simplifying x + -1 = -2.915475947 Reorder the terms: -1 + x = -2.915475947 Solving -1 + x = -2.915475947 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '1' to each side of the equation. -1 + 1 + x = -2.915475947 + 1 Combine like terms: -1 + 1 = 0 0 + x = -2.915475947 + 1 x = -2.915475947 + 1 Combine like terms: -2.915475947 + 1 = -1.915475947 x = -1.915475947 Simplifying x = -1.915475947

Solution

The solution to the problem is based on the solutions from the subproblems. x = {3.915475947, -1.915475947}

See similar equations:

| lgx=25 | | 45=(2x+3)(3x-4) | | 4x-2=2-2x | | 8n^2-96n+256=0 | | 2×y/3=16/27 | | 3x(6+2)= | | 40+16.25x+8.50x=40+15.25+9.50x | | 1x/4=8 | | 5x^3-21x^2+14x-2=0 | | 8n^2=-3+8n | | y=3x^2+5x-2 | | 11.1c-2.4=-8.3c+7.3 | | x*3=2x+4 | | -2+9x=5x-5 | | 4np-7=3m+7 | | 6b^2+3b=-4 | | y-2=3y/4 | | 1/2x-5=2 | | 5sec^2x+4tanx=5 | | (2x-48)=x+32 | | 5sec^2(x)+4tanx=5 | | 4y+15=2y+3 | | y/2-832 | | -15n-3=6+18n+6 | | 7n-9=5(n+3) | | 3a-4=-1 | | x-2y+-5=0 | | x+32=2x+13 | | .3x^2+2x-1=0 | | x(4x-7)=8 | | (3w-7)(w)=40 | | 0=6x^2-x-5 |

Equations solver categories