82.5=0.5x*(9+21)

Solution for 82.5=0.5x*(9+21) equation:

Simplifying
82.5 = 0.5x(9 + 21)

Combine like terms: 9 + 21 = 30
82.5 = 0.5x(30)

Reorder the terms for easier multiplication:
82.5 = 0.5 * 30x

Multiply 0.5 * 30
82.5 = 15x

Solving
82.5 = 15x

Solving for variable 'x'.

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

Add '-15x' to each side of the equation.
82.5 + -15x = 15x + -15x

Combine like terms: 15x + -15x = 0
82.5 + -15x = 0

Add '-82.5' to each side of the equation.
82.5 + -82.5 + -15x = 0 + -82.5

Combine like terms: 82.5 + -82.5 = 0.0
0.0 + -15x = 0 + -82.5
-15x = 0 + -82.5

Combine like terms: 0 + -82.5 = -82.5
-15x = -82.5

Divide each side by '-15'.
x = 5.5

Simplifying
x = 5.5