105=63+r

Solution for 105=63+r equation:

Simplifying
105 = 63 + r

Solving
105 = 63 + r

Solving for variable 'r'.

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

Add '-1r' to each side of the equation.
105 + -1r = 63 + r + -1r

Combine like terms: r + -1r = 0
105 + -1r = 63 + 0
105 + -1r = 63

Add '-105' to each side of the equation.
105 + -105 + -1r = 63 + -105

Combine like terms: 105 + -105 = 0
0 + -1r = 63 + -105
-1r = 63 + -105

Combine like terms: 63 + -105 = -42
-1r = -42

Divide each side by '-1'.
r = 42

Simplifying
r = 42