8r^2+7=5r+4

Solution for 8r^2+7=5r+4 equation:

Simplifying
8r2 + 7 = 5r + 4

Reorder the terms:
7 + 8r2 = 5r + 4

Reorder the terms:
7 + 8r2 = 4 + 5r

Solving
7 + 8r2 = 4 + 5r

Solving for variable 'r'.

Reorder the terms:
7 + -4 + -5r + 8r2 = 4 + 5r + -4 + -5r

Combine like terms: 7 + -4 = 3
3 + -5r + 8r2 = 4 + 5r + -4 + -5r

Reorder the terms:
3 + -5r + 8r2 = 4 + -4 + 5r + -5r

Combine like terms: 4 + -4 = 0
3 + -5r + 8r2 = 0 + 5r + -5r
3 + -5r + 8r2 = 5r + -5r

Combine like terms: 5r + -5r = 0
3 + -5r + 8r2 = 0

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

Divide each side by '8'.
0.375 + -0.625r + r2 = 0

Move the constant term to the right:

Add '-0.375' to each side of the equation.
0.375 + -0.625r + -0.375 + r2 = 0 + -0.375

Reorder the terms:
0.375 + -0.375 + -0.625r + r2 = 0 + -0.375

Combine like terms: 0.375 + -0.375 = 0.000
0.000 + -0.625r + r2 = 0 + -0.375
-0.625r + r2 = 0 + -0.375

Combine like terms: 0 + -0.375 = -0.375
-0.625r + r2 = -0.375

The r term is -0.625r.  Take half its coefficient (-0.3125).
Square it (0.09765625) and add it to both sides.

Add '0.09765625' to each side of the equation.
-0.625r + 0.09765625 + r2 = -0.375 + 0.09765625

Reorder the terms:
0.09765625 + -0.625r + r2 = -0.375 + 0.09765625

Combine like terms: -0.375 + 0.09765625 = -0.27734375
0.09765625 + -0.625r + r2 = -0.27734375

Factor a perfect square on the left side:
(r + -0.3125)(r + -0.3125) = -0.27734375

Can't calculate square root of the right side.

The solution to this equation could not be determined.