Exercise algebra.equations.linear.balance

Description
Solve a linear equation using only balance rules.

Derivation

3*x-20 == -1-5*x

⇒ algebra.equations.linear.balance.var-left-plus, term=5*x

8*x-20 == -1

⇒ algebra.equations.linear.balance.con-right-plus, term=20

8*x == 19

⇒ algebra.equations.linear.balance.scale-to-one, factor=8

x == 19/8