Exercise algebra.equations.linear.balance
Description
Solve a linear equation using only balance rules.
Derivation
8*x-9 == 9*x-4
⇒ algebra.equations.linear.balance.var-right-minus, term=8*x-9 == x-4
⇒ algebra.equations.linear.balance.con-left-plus, term=4-5 == x
⇒ algebra.equations.linear.flipx == -5