Exercise algebra.equations.linear.balance

Description
Solve a linear equation using only balance rules.

Derivation

-4 == -2*x-3

⇒ algebra.equations.linear.balance.con-left-plus, term=3

-1 == -2*x

⇒ algebra.equations.linear.balance.scale-to-one, factor=-2

1/2 == x

⇒ algebra.equations.linear.flip

x == 1/2