d^2+16d=-9

Simple and best practice solution for d^2+16d=-9 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+16d=-9 equation:


Simplifying
d2 + 16d = -9

Reorder the terms:
16d + d2 = -9

Solving
16d + d2 = -9

Solving for variable 'd'.

Reorder the terms:
9 + 16d + d2 = -9 + 9

Combine like terms: -9 + 9 = 0
9 + 16d + d2 = 0

Begin completing the square.

Move the constant term to the right:

Add '-9' to each side of the equation.
9 + 16d + -9 + d2 = 0 + -9

Reorder the terms:
9 + -9 + 16d + d2 = 0 + -9

Combine like terms: 9 + -9 = 0
0 + 16d + d2 = 0 + -9
16d + d2 = 0 + -9

Combine like terms: 0 + -9 = -9
16d + d2 = -9

The d term is 16d.  Take half its coefficient (8).
Square it (64) and add it to both sides.

Add '64' to each side of the equation.
16d + 64 + d2 = -9 + 64

Reorder the terms:
64 + 16d + d2 = -9 + 64

Combine like terms: -9 + 64 = 55
64 + 16d + d2 = 55

Factor a perfect square on the left side:
(d + 8)(d + 8) = 55

Calculate the square root of the right side: 7.416198487

Break this problem into two subproblems by setting 
(d + 8) equal to 7.416198487 and -7.416198487.

Subproblem 1

d + 8 = 7.416198487 Simplifying d + 8 = 7.416198487 Reorder the terms: 8 + d = 7.416198487 Solving 8 + d = 7.416198487 Solving for variable 'd'. Move all terms containing d to the left, all other terms to the right. Add '-8' to each side of the equation. 8 + -8 + d = 7.416198487 + -8 Combine like terms: 8 + -8 = 0 0 + d = 7.416198487 + -8 d = 7.416198487 + -8 Combine like terms: 7.416198487 + -8 = -0.583801513 d = -0.583801513 Simplifying d = -0.583801513

Subproblem 2

d + 8 = -7.416198487 Simplifying d + 8 = -7.416198487 Reorder the terms: 8 + d = -7.416198487 Solving 8 + d = -7.416198487 Solving for variable 'd'. Move all terms containing d to the left, all other terms to the right. Add '-8' to each side of the equation. 8 + -8 + d = -7.416198487 + -8 Combine like terms: 8 + -8 = 0 0 + d = -7.416198487 + -8 d = -7.416198487 + -8 Combine like terms: -7.416198487 + -8 = -15.416198487 d = -15.416198487 Simplifying d = -15.416198487

Solution

The solution to the problem is based on the solutions from the subproblems. d = {-0.583801513, -15.416198487}

See similar equations:

| 1/2c=25 | | 5h+2h-3=18 | | 2/k=-4 | | 9x+8=3+5x | | 2x+4(x-3)=5(x+3)-18 | | .5(6z+8)-2=2(z-10) | | 14p-9p=70 | | ln(x+2)=2 | | 3x+111=224 | | 2x+3y+50=180 | | 2(x-0.6)+0.3=1 | | x+x(0.13)=1306.28 | | =6+2y+54+4y | | 3(2-y)=3 | | 2x-28=57 | | ax+5a=4-6x | | (S-2)/5=3 | | 41x^2=2 | | 5k^2-18k+11=-5 | | 4u^2+17u+15=0 | | log(x^2-4x-2)=1 | | 1x/5=10 | | 6x-2x+8=-12 | | -1=2y-(3) | | 10=(r^4-1)/(r^2-1) | | 2x(x-6)=8 | | -1=2y(-3) | | (x-4y)dx+(3x-2y)dy=0 | | 70=(2x+4)*x | | 8z+9-2z+6= | | x^3-x^2-2x+24=0 | | -36+6x=x+34 |

Equations solver categories