Exercise algebra.equations.linear.balance

Description
Solve a linear equation using only balance rules.

Derivation

-x+13 == 4*x

⇒ algebra.equations.linear.balance.var-right-plus, term=x

13 == 5*x

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

13/5 == x

⇒ algebra.equations.linear.flip

x == 13/5