Exercise algebra.equations.linear.balance

Description
Solve a linear equation using only balance rules.

Derivation

3+6*x == 3*x+24

⇒ algebra.equations.linear.balance.var-left-minus, term=3*x

3+3*x == 24

⇒ algebra.equations.linear.balance.con-right-minus, term=3

3*x == 21

⇒ algebra.equations.linear.balance.scale-to-one, factor=3

x == 7