r^2+25r=7

Simple and best practice solution for r^2+25r=7 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 r^2+25r=7 equation:


Simplifying
r2 + 25r = 7

Reorder the terms:
25r + r2 = 7

Solving
25r + r2 = 7

Solving for variable 'r'.

Reorder the terms:
-7 + 25r + r2 = 7 + -7

Combine like terms: 7 + -7 = 0
-7 + 25r + r2 = 0

Begin completing the square.

Move the constant term to the right:

Add '7' to each side of the equation.
-7 + 25r + 7 + r2 = 0 + 7

Reorder the terms:
-7 + 7 + 25r + r2 = 0 + 7

Combine like terms: -7 + 7 = 0
0 + 25r + r2 = 0 + 7
25r + r2 = 0 + 7

Combine like terms: 0 + 7 = 7
25r + r2 = 7

The r term is 25r.  Take half its coefficient (12.5).
Square it (156.25) and add it to both sides.

Add '156.25' to each side of the equation.
25r + 156.25 + r2 = 7 + 156.25

Reorder the terms:
156.25 + 25r + r2 = 7 + 156.25

Combine like terms: 7 + 156.25 = 163.25
156.25 + 25r + r2 = 163.25

Factor a perfect square on the left side:
(r + 12.5)(r + 12.5) = 163.25

Calculate the square root of the right side: 12.776932339

Break this problem into two subproblems by setting 
(r + 12.5) equal to 12.776932339 and -12.776932339.

Subproblem 1

r + 12.5 = 12.776932339 Simplifying r + 12.5 = 12.776932339 Reorder the terms: 12.5 + r = 12.776932339 Solving 12.5 + r = 12.776932339 Solving for variable 'r'. Move all terms containing r to the left, all other terms to the right. Add '-12.5' to each side of the equation. 12.5 + -12.5 + r = 12.776932339 + -12.5 Combine like terms: 12.5 + -12.5 = 0.0 0.0 + r = 12.776932339 + -12.5 r = 12.776932339 + -12.5 Combine like terms: 12.776932339 + -12.5 = 0.276932339 r = 0.276932339 Simplifying r = 0.276932339

Subproblem 2

r + 12.5 = -12.776932339 Simplifying r + 12.5 = -12.776932339 Reorder the terms: 12.5 + r = -12.776932339 Solving 12.5 + r = -12.776932339 Solving for variable 'r'. Move all terms containing r to the left, all other terms to the right. Add '-12.5' to each side of the equation. 12.5 + -12.5 + r = -12.776932339 + -12.5 Combine like terms: 12.5 + -12.5 = 0.0 0.0 + r = -12.776932339 + -12.5 r = -12.776932339 + -12.5 Combine like terms: -12.776932339 + -12.5 = -25.276932339 r = -25.276932339 Simplifying r = -25.276932339

Solution

The solution to the problem is based on the solutions from the subproblems. r = {0.276932339, -25.276932339}

See similar equations:

| 0-c=6 | | 12x^6-19x^4+19x^3= | | 25zsquared=81 | | 82=2d+3.26(8+6) | | a6/a4= | | a6/a4 | | 2820=64t+980 | | (4x+19)+(28x-2)=360 | | 7a+8b=10x | | -4(u+4)+6u= | | -3a+5(-a-5)=-35-5a | | .06875=2w+.1875 | | 15y/8x=9 | | 11*n=9000 | | 4x+12y=180y | | 11*n=8000 | | (-9)-t=26 | | 5y^2=6-2y | | A(4)=-2 | | -12x^3y^5-9x^2y^2+12xy^3=0 | | x^3-12x^2+x=0 | | -5y-y=-4x-14 | | 10y^4/5y^2= | | 32=-0.002h+76 | | 10a-5=-5 | | (x^2-x+7)(x-6)= | | f(5)=.72(5)+2 | | x^2+4y^3=0 | | 1/3×2/5 | | x^2+xy+y^2-4x-4y=0 | | 0.6x=2.2-4 | | -11=2(x+4)-(x-3) |

Equations solver categories