2r-3=r^2+81

Simple and best practice solution for 2r-3=r^2+81 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 2r-3=r^2+81 equation:


Simplifying
2r + -3 = r2 + 81

Reorder the terms:
-3 + 2r = r2 + 81

Reorder the terms:
-3 + 2r = 81 + r2

Solving
-3 + 2r = 81 + r2

Solving for variable 'r'.

Reorder the terms:
-3 + -81 + 2r + -1r2 = 81 + r2 + -81 + -1r2

Combine like terms: -3 + -81 = -84
-84 + 2r + -1r2 = 81 + r2 + -81 + -1r2

Reorder the terms:
-84 + 2r + -1r2 = 81 + -81 + r2 + -1r2

Combine like terms: 81 + -81 = 0
-84 + 2r + -1r2 = 0 + r2 + -1r2
-84 + 2r + -1r2 = r2 + -1r2

Combine like terms: r2 + -1r2 = 0
-84 + 2r + -1r2 = 0

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

Divide each side by '-1'.
84 + -2r + r2 = 0

Move the constant term to the right:

Add '-84' to each side of the equation.
84 + -2r + -84 + r2 = 0 + -84

Reorder the terms:
84 + -84 + -2r + r2 = 0 + -84

Combine like terms: 84 + -84 = 0
0 + -2r + r2 = 0 + -84
-2r + r2 = 0 + -84

Combine like terms: 0 + -84 = -84
-2r + r2 = -84

The r term is -2r.  Take half its coefficient (-1).
Square it (1) and add it to both sides.

Add '1' to each side of the equation.
-2r + 1 + r2 = -84 + 1

Reorder the terms:
1 + -2r + r2 = -84 + 1

Combine like terms: -84 + 1 = -83
1 + -2r + r2 = -83

Factor a perfect square on the left side:
(r + -1)(r + -1) = -83

Can't calculate square root of the right side.

The solution to this equation could not be determined.

See similar equations:

| 6-2x+6x=-2(-8x+3) | | x-(0.18*x)=16.03 | | -6x-15=4+35 | | 16-a+4a=4 | | -76/-19 | | 5+3x=5+x | | 0.543=x^2/(0.03-x)^2 | | 7ax-35xy+aw-wy= | | p^2(16p^6q^8)^1/2 | | 8y+10=2(y+11) | | e^3x-5=32 | | f(x)=500(1.05)x | | 7-2(x+1)=28 | | (1/5)x-(2/3)x-2=-(2/5)x | | 2x+3x+x=312 | | 9x=4x-30 | | -5/9 | | x^2+200x-480000=0 | | 10p-(6p-3)+(-4p+5)= | | (6b+4)*(6b+4)= | | 3(2n-4)=24 | | 10p-(6p-3)+(-4+5)= | | x^2-200x-480000=0 | | 2x+14=3x+36 | | 0.02(x-8)+0.08x=0.20x-0.9 | | f(x)=ln(7+8x) | | 10-6x=5-7x | | y-5=-2/3(x-4) | | 3c^2-8c-16= | | 5x+y=-35 | | 3c-8c-16= | | -3.9x=31.2 |

Equations solver categories