d^2-18d+81=13

Simple and best practice solution for d^2-18d+81=13 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 d^2-18d+81=13 equation: 


Simplifying
d2 + -18d + 81 = 13

Reorder the terms:
81 + -18d + d2 = 13

Solving
81 + -18d + d2 = 13

Solving for variable 'd'.

Reorder the terms:
81 + -13 + -18d + d2 = 13 + -13

Combine like terms: 81 + -13 = 68
68 + -18d + d2 = 13 + -13

Combine like terms: 13 + -13 = 0
68 + -18d + d2 = 0

Begin completing the square.

Move the constant term to the right:

Add '-68' to each side of the equation.
68 + -18d + -68 + d2 = 0 + -68

Reorder the terms:
68 + -68 + -18d + d2 = 0 + -68

Combine like terms: 68 + -68 = 0
0 + -18d + d2 = 0 + -68
-18d + d2 = 0 + -68

Combine like terms: 0 + -68 = -68
-18d + d2 = -68

The d term is -18d.  Take half its coefficient (-9).
Square it (81) and add it to both sides.

Add '81' to each side of the equation.
-18d + 81 + d2 = -68 + 81

Reorder the terms:
81 + -18d + d2 = -68 + 81

Combine like terms: -68 + 81 = 13
81 + -18d + d2 = 13

Factor a perfect square on the left side:
(d + -9)(d + -9) = 13

Calculate the square root of the right side: 3.605551275

Break this problem into two subproblems by setting 
(d + -9) equal to 3.605551275 and -3.605551275.


Subproblem 1
d + -9 = 3.605551275

Simplifying
d + -9 = 3.605551275

Reorder the terms:
-9 + d = 3.605551275

Solving
-9 + d = 3.605551275

Solving for variable 'd'.

Move all terms containing d to the left, all other terms to the right.

Add '9' to each side of the equation.
-9 + 9 + d = 3.605551275 + 9

Combine like terms: -9 + 9 = 0
0 + d = 3.605551275 + 9
d = 3.605551275 + 9

Combine like terms: 3.605551275 + 9 = 12.605551275
d = 12.605551275

Simplifying
d = 12.605551275


Subproblem 2
d + -9 = -3.605551275

Simplifying
d + -9 = -3.605551275

Reorder the terms:
-9 + d = -3.605551275

Solving
-9 + d = -3.605551275

Solving for variable 'd'.

Move all terms containing d to the left, all other terms to the right.

Add '9' to each side of the equation.
-9 + 9 + d = -3.605551275 + 9

Combine like terms: -9 + 9 = 0
0 + d = -3.605551275 + 9
d = -3.605551275 + 9

Combine like terms: -3.605551275 + 9 = 5.394448725
d = 5.394448725

Simplifying
d = 5.394448725


Solution
The solution to the problem is based on the solutions
from the subproblems.
d = {12.605551275, 5.394448725}

See similar equations:

| 5m+6km-8hm= | | =i^103 | | 4s^2-8=0 | | .66y=12 | | 24=-.33t | | .20n=-9 | | 4s^2-3s=0 | | 3(x^2-14x+49)=-14 | | 9s^2+2s-9=0 | | 3s^2-9s-6=0 | | 6(1+2x)-(8x-7)=17 | | w-11=3 | | 2(x)-8=x-7 | | 5v+25= | | 5(15x+5)=415 | | cos(x)=11x | | 7x^2+5x+h=0 | | ln(x+35)-ln(x-1)=ln(x-5) | | 6s^2+5s=0 | | 2+10(4x+5)= | | 3(x^2-14x)=-14 | | 6(-3x+4)=-120 | | .2x+.3y=.23(100) | | 5s^2-5s-7=0 | | -2s-7=5 | | 8s^2-6s-8=0 | | 48=x(16-x) | | 5w-7w+6+8w= | | 2s^2-3s+8=0 | | 4s+4=-28 | | 2s^2-6s+2=0 | | 6s^2-7s+1=0 |

Equations solver categories