Exercise algebra.equations.linear.balance

Description
Solve a linear equation using only balance rules.

Derivation

-1/2*x == 2*x-13/2

⇒ algebra.equations.linear.balance.remove-div, factor=2

-x == 4*x-13

⇒ algebra.equations.linear.balance.var-left-minus, term=4*x

-5*x == -13

⇒ algebra.equations.linear.balance.scale-to-one, factor=-5

x == 13/5