4(r+2.3)-9r=13.5

Solution for 4(r+2.3)-9r=13.5 equation:

Simplifying
4(r + 2.3) + -9r = 13.5

Reorder the terms:
4(2.3 + r) + -9r = 13.5
(2.3 * 4 + r * 4) + -9r = 13.5
(9.2 + 4r) + -9r = 13.5

Combine like terms: 4r + -9r = -5r
9.2 + -5r = 13.5

Solving
9.2 + -5r = 13.5

Solving for variable 'r'.

Move all terms containing r to the left, all other terms to the right.

Add '-9.2' to each side of the equation.
9.2 + -9.2 + -5r = 13.5 + -9.2

Combine like terms: 9.2 + -9.2 = 0.0
0.0 + -5r = 13.5 + -9.2
-5r = 13.5 + -9.2

Combine like terms: 13.5 + -9.2 = 4.3
-5r = 4.3

Divide each side by '-5'.
r = -0.86

Simplifying
r = -0.86