x^2=3x+15

Simple and best practice solution for x^2=3x+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 x^2=3x+15 equation:


Simplifying
x2 = 3x + 15

Reorder the terms:
x2 = 15 + 3x

Solving
x2 = 15 + 3x

Solving for variable 'x'.

Reorder the terms:
-15 + -3x + x2 = 15 + 3x + -15 + -3x

Reorder the terms:
-15 + -3x + x2 = 15 + -15 + 3x + -3x

Combine like terms: 15 + -15 = 0
-15 + -3x + x2 = 0 + 3x + -3x
-15 + -3x + x2 = 3x + -3x

Combine like terms: 3x + -3x = 0
-15 + -3x + x2 = 0

Begin completing the square.

Move the constant term to the right:

Add '15' to each side of the equation.
-15 + -3x + 15 + x2 = 0 + 15

Reorder the terms:
-15 + 15 + -3x + x2 = 0 + 15

Combine like terms: -15 + 15 = 0
0 + -3x + x2 = 0 + 15
-3x + x2 = 0 + 15

Combine like terms: 0 + 15 = 15
-3x + x2 = 15

The x term is -3x.  Take half its coefficient (-1.5).
Square it (2.25) and add it to both sides.

Add '2.25' to each side of the equation.
-3x + 2.25 + x2 = 15 + 2.25

Reorder the terms:
2.25 + -3x + x2 = 15 + 2.25

Combine like terms: 15 + 2.25 = 17.25
2.25 + -3x + x2 = 17.25

Factor a perfect square on the left side:
(x + -1.5)(x + -1.5) = 17.25

Calculate the square root of the right side: 4.153311931

Break this problem into two subproblems by setting 
(x + -1.5) equal to 4.153311931 and -4.153311931.

Subproblem 1

x + -1.5 = 4.153311931 Simplifying x + -1.5 = 4.153311931 Reorder the terms: -1.5 + x = 4.153311931 Solving -1.5 + x = 4.153311931 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '1.5' to each side of the equation. -1.5 + 1.5 + x = 4.153311931 + 1.5 Combine like terms: -1.5 + 1.5 = 0.0 0.0 + x = 4.153311931 + 1.5 x = 4.153311931 + 1.5 Combine like terms: 4.153311931 + 1.5 = 5.653311931 x = 5.653311931 Simplifying x = 5.653311931

Subproblem 2

x + -1.5 = -4.153311931 Simplifying x + -1.5 = -4.153311931 Reorder the terms: -1.5 + x = -4.153311931 Solving -1.5 + x = -4.153311931 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '1.5' to each side of the equation. -1.5 + 1.5 + x = -4.153311931 + 1.5 Combine like terms: -1.5 + 1.5 = 0.0 0.0 + x = -4.153311931 + 1.5 x = -4.153311931 + 1.5 Combine like terms: -4.153311931 + 1.5 = -2.653311931 x = -2.653311931 Simplifying x = -2.653311931

Solution

The solution to the problem is based on the solutions from the subproblems. x = {5.653311931, -2.653311931}

See similar equations:

| 5p+3q=31 | | 3y-4x+1=0 | | 15b^2+34b-16=0 | | 8x^2+48x-216=0 | | ln(2)=x^2+x | | b^2+7b=7b+9 | | t^2=6t-9 | | -3/7g+(-1/3)g | | 2+2(x+3)=x+4 | | 4n-(n-1)+5= | | 4x(6-x)(5-x)=50 | | 2d-3d=6 | | (12-2x)(10-2x)x=50 | | 3000=1600+0.1s+0.15(s-5000) | | y-5/y-y/y+1 | | 4x^3+44x^2-120x-50=0 | | 8+7i=0 | | (n-2)4= | | In(x-1)=8 | | X/9+4x=8 | | d=-4c+13 | | 6c+6d=-12 | | 2x+27=11x-81 | | 6q+25q+24=0 | | 4t+3t-2m-3m= | | r=2m+2z | | 9r^2+6r=1 | | 5(4x-6)-(3x+3)= | | 3x+28=10-28 | | N+43=54 | | x^2-15x-25= | | 1/16(50)^2-(y-28)^2=0 |

Equations solver categories