1.25x^2-9x-16=0

Simple and best practice solution for 1.25x^2-9x-16=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 1.25x^2-9x-16=0 equation:


Simplifying
1.25x2 + -9x + -16 = 0

Reorder the terms:
-16 + -9x + 1.25x2 = 0

Solving
-16 + -9x + 1.25x2 = 0

Solving for variable 'x'.

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

Divide each side by '1.25'.
-12.8 + -7.2x + x2 = 0

Move the constant term to the right:

Add '12.8' to each side of the equation.
-12.8 + -7.2x + 12.8 + x2 = 0 + 12.8

Reorder the terms:
-12.8 + 12.8 + -7.2x + x2 = 0 + 12.8

Combine like terms: -12.8 + 12.8 = 0.0
0.0 + -7.2x + x2 = 0 + 12.8
-7.2x + x2 = 0 + 12.8

Combine like terms: 0 + 12.8 = 12.8
-7.2x + x2 = 12.8

The x term is -7.2x.  Take half its coefficient (-3.6).
Square it (12.96) and add it to both sides.

Add '12.96' to each side of the equation.
-7.2x + 12.96 + x2 = 12.8 + 12.96

Reorder the terms:
12.96 + -7.2x + x2 = 12.8 + 12.96

Combine like terms: 12.8 + 12.96 = 25.76
12.96 + -7.2x + x2 = 25.76

Factor a perfect square on the left side:
(x + -3.6)(x + -3.6) = 25.76

Calculate the square root of the right side: 5.075431016

Break this problem into two subproblems by setting 
(x + -3.6) equal to 5.075431016 and -5.075431016.

Subproblem 1

x + -3.6 = 5.075431016 Simplifying x + -3.6 = 5.075431016 Reorder the terms: -3.6 + x = 5.075431016 Solving -3.6 + x = 5.075431016 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '3.6' to each side of the equation. -3.6 + 3.6 + x = 5.075431016 + 3.6 Combine like terms: -3.6 + 3.6 = 0.0 0.0 + x = 5.075431016 + 3.6 x = 5.075431016 + 3.6 Combine like terms: 5.075431016 + 3.6 = 8.675431016 x = 8.675431016 Simplifying x = 8.675431016

Subproblem 2

x + -3.6 = -5.075431016 Simplifying x + -3.6 = -5.075431016 Reorder the terms: -3.6 + x = -5.075431016 Solving -3.6 + x = -5.075431016 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '3.6' to each side of the equation. -3.6 + 3.6 + x = -5.075431016 + 3.6 Combine like terms: -3.6 + 3.6 = 0.0 0.0 + x = -5.075431016 + 3.6 x = -5.075431016 + 3.6 Combine like terms: -5.075431016 + 3.6 = -1.475431016 x = -1.475431016 Simplifying x = -1.475431016

Solution

The solution to the problem is based on the solutions from the subproblems. x = {8.675431016, -1.475431016}

See similar equations:

| 3(3n+3)=6(4n+6)+6 | | 2(-6x-18/7) | | 14/5/1/5=49/2/7/6 | | n/50=2/100 | | -3(2x-1)+7=-6x+10 | | 2a+8=6 | | 5x-25=x+75 | | t=27-1/2(w-k) | | (x-1)=x-1 | | 5(4x-1)=20x-5 | | 15/5/3=50/n | | 0.10(y-6)+0.33y=0.03y-0.40 | | 7+0.25r=-17 | | 0.72+0.24t=2.64t-0.72 | | -25=0.2h+5 | | 1.8x+2.8=2.5+21 | | 0.5j+4=-15 | | -7/8*-3/8 | | 5/2/10/4=50n | | .2x-.8(5-4x)=-.7(x-6) | | (x-3)3=294 | | x-30=14-3(x) | | 4.7x+2=2.5x-9 | | -6(x-2)-6=6 | | 3(x)+4=18(x) | | 4x-6(9-x)=12 | | 14+3x=6x-4 | | 3z+9=15 | | 4q=q+12 | | 2x^4-160=0 | | (4x-2(x-4))/3=8 | | [7(z+4)-16]-[2(z-3)+1]= |

Equations solver categories