z^2-5z-7=0

Simple and best practice solution for z^2-5z-7=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 z^2-5z-7=0 equation:


Simplifying
z2 + -5z + -7 = 0

Reorder the terms:
-7 + -5z + z2 = 0

Solving
-7 + -5z + z2 = 0

Solving for variable 'z'.

Begin completing the square.

Move the constant term to the right:

Add '7' to each side of the equation.
-7 + -5z + 7 + z2 = 0 + 7

Reorder the terms:
-7 + 7 + -5z + z2 = 0 + 7

Combine like terms: -7 + 7 = 0
0 + -5z + z2 = 0 + 7
-5z + z2 = 0 + 7

Combine like terms: 0 + 7 = 7
-5z + z2 = 7

The z term is -5z.  Take half its coefficient (-2.5).
Square it (6.25) and add it to both sides.

Add '6.25' to each side of the equation.
-5z + 6.25 + z2 = 7 + 6.25

Reorder the terms:
6.25 + -5z + z2 = 7 + 6.25

Combine like terms: 7 + 6.25 = 13.25
6.25 + -5z + z2 = 13.25

Factor a perfect square on the left side:
(z + -2.5)(z + -2.5) = 13.25

Calculate the square root of the right side: 3.640054945

Break this problem into two subproblems by setting 
(z + -2.5) equal to 3.640054945 and -3.640054945.

Subproblem 1

z + -2.5 = 3.640054945 Simplifying z + -2.5 = 3.640054945 Reorder the terms: -2.5 + z = 3.640054945 Solving -2.5 + z = 3.640054945 Solving for variable 'z'. Move all terms containing z to the left, all other terms to the right. Add '2.5' to each side of the equation. -2.5 + 2.5 + z = 3.640054945 + 2.5 Combine like terms: -2.5 + 2.5 = 0.0 0.0 + z = 3.640054945 + 2.5 z = 3.640054945 + 2.5 Combine like terms: 3.640054945 + 2.5 = 6.140054945 z = 6.140054945 Simplifying z = 6.140054945

Subproblem 2

z + -2.5 = -3.640054945 Simplifying z + -2.5 = -3.640054945 Reorder the terms: -2.5 + z = -3.640054945 Solving -2.5 + z = -3.640054945 Solving for variable 'z'. Move all terms containing z to the left, all other terms to the right. Add '2.5' to each side of the equation. -2.5 + 2.5 + z = -3.640054945 + 2.5 Combine like terms: -2.5 + 2.5 = 0.0 0.0 + z = -3.640054945 + 2.5 z = -3.640054945 + 2.5 Combine like terms: -3.640054945 + 2.5 = -1.140054945 z = -1.140054945 Simplifying z = -1.140054945

Solution

The solution to the problem is based on the solutions from the subproblems. z = {6.140054945, -1.140054945}

See similar equations:

| 10-5x^2+3(2+6)= | | 7187=x+.293x | | 49x^2+28x-96=0 | | 28y+7= | | 6+8(x)=62 | | 30x-62=28 | | 1525=10x+5(195-x) | | y=3z-3 | | 177+43+5x+2x=360 | | 2x^2-2x=612 | | y=3*z | | In(x+6)=In(x)+In(6) | | 8+9=-3 | | (2x+3)-(4x+7)=5+2(4x+1) | | z=12y-2x | | 3z^2-15z-21=0 | | 6+8*x=62 | | y=1.25x+4.10 | | 4x^2+20x-49=0 | | -2x+4x=33x+39 | | X-37=20 | | (2x+3)-(4x+7)= | | 3.5q-1.1-5.6q=-3.1q-3.7 | | 6x-5x+4=-4 | | 0.125(x-24)=0.875 | | x/9-4=9 | | 13+h=7 | | 4a^3-4a^2+68a+42=0 | | 5t+16=5 | | 30x-80=40 | | 65.5=5x-3 | | 4x^2-28x-3y+30=0 |

Equations solver categories