0=c^2-7c-40

Simple and best practice solution for 0=c^2-7c-40 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 0=c^2-7c-40 equation:


Simplifying
0 = c2 + -7c + -40

Reorder the terms:
0 = -40 + -7c + c2

Solving
0 = -40 + -7c + c2

Solving for variable 'c'.

Combine like terms: 0 + 40 = 40
40 + 7c + -1c2 = -40 + -7c + c2 + 40 + 7c + -1c2

Reorder the terms:
40 + 7c + -1c2 = -40 + 40 + -7c + 7c + c2 + -1c2

Combine like terms: -40 + 40 = 0
40 + 7c + -1c2 = 0 + -7c + 7c + c2 + -1c2
40 + 7c + -1c2 = -7c + 7c + c2 + -1c2

Combine like terms: -7c + 7c = 0
40 + 7c + -1c2 = 0 + c2 + -1c2
40 + 7c + -1c2 = c2 + -1c2

Combine like terms: c2 + -1c2 = 0
40 + 7c + -1c2 = 0

Begin completing the square.  Divide all terms by
-1 the coefficient of the squared term: 

Divide each side by '-1'.
-40 + -7c + c2 = 0

Move the constant term to the right:

Add '40' to each side of the equation.
-40 + -7c + 40 + c2 = 0 + 40

Reorder the terms:
-40 + 40 + -7c + c2 = 0 + 40

Combine like terms: -40 + 40 = 0
0 + -7c + c2 = 0 + 40
-7c + c2 = 0 + 40

Combine like terms: 0 + 40 = 40
-7c + c2 = 40

The c term is -7c.  Take half its coefficient (-3.5).
Square it (12.25) and add it to both sides.

Add '12.25' to each side of the equation.
-7c + 12.25 + c2 = 40 + 12.25

Reorder the terms:
12.25 + -7c + c2 = 40 + 12.25

Combine like terms: 40 + 12.25 = 52.25
12.25 + -7c + c2 = 52.25

Factor a perfect square on the left side:
(c + -3.5)(c + -3.5) = 52.25

Calculate the square root of the right side: 7.228416147

Break this problem into two subproblems by setting 
(c + -3.5) equal to 7.228416147 and -7.228416147.

Subproblem 1

c + -3.5 = 7.228416147 Simplifying c + -3.5 = 7.228416147 Reorder the terms: -3.5 + c = 7.228416147 Solving -3.5 + c = 7.228416147 Solving for variable 'c'. Move all terms containing c to the left, all other terms to the right. Add '3.5' to each side of the equation. -3.5 + 3.5 + c = 7.228416147 + 3.5 Combine like terms: -3.5 + 3.5 = 0.0 0.0 + c = 7.228416147 + 3.5 c = 7.228416147 + 3.5 Combine like terms: 7.228416147 + 3.5 = 10.728416147 c = 10.728416147 Simplifying c = 10.728416147

Subproblem 2

c + -3.5 = -7.228416147 Simplifying c + -3.5 = -7.228416147 Reorder the terms: -3.5 + c = -7.228416147 Solving -3.5 + c = -7.228416147 Solving for variable 'c'. Move all terms containing c to the left, all other terms to the right. Add '3.5' to each side of the equation. -3.5 + 3.5 + c = -7.228416147 + 3.5 Combine like terms: -3.5 + 3.5 = 0.0 0.0 + c = -7.228416147 + 3.5 c = -7.228416147 + 3.5 Combine like terms: -7.228416147 + 3.5 = -3.728416147 c = -3.728416147 Simplifying c = -3.728416147

Solution

The solution to the problem is based on the solutions from the subproblems. c = {10.728416147, -3.728416147}

See similar equations:

| 3x+-2=2x+-5 | | (-13)-(-8)-(-7)= | | B-3.8=3(b+5) | | 3X+1=90-45 | | 10=5(k+2) | | -3(5x+-1)=-57 | | Y=-25/x | | 4(3x-2)=5x+66 | | 3=m(4)+b | | 5/9v≤45 | | 2(x+3)=7x+26 | | 8(-1+0.5y)-4y=-12 | | 4(x-5)=3(x-2)-2(x+2) | | n=2+4s | | 2(x+2)=7x+26 | | 5u-10-19u+47= | | 48x-24y=-48 | | y/3=3.84 | | 3x+36=84 | | n=2s+2(s+1) | | 6k+2=62 | | 4x+9=x(2x+1) | | 45(4x+4)=40(5x+1) | | 12m+16+8m=89 | | 19p+12+11p+25= | | 6m=14p-4m+16 | | 38.2xj=0.573 | | 3x+26=56 | | -3+4=2x+19 | | 2x^2+17x=-35 | | 98+13m=332 | | e=e+2 |

Equations solver categories