Exercise algebra.equations.linear.balance

Description
Solve a linear equation using only balance rules.

Derivation

-4*x+9 == 3*x+2

⇒ algebra.equations.linear.balance.var-right-plus, term=4*x

9 == 7*x+2

⇒ algebra.equations.linear.balance.con-left-minus, term=2

7 == 7*x

⇒ algebra.equations.linear.balance.scale-to-one, factor=7

1 == x

⇒ algebra.equations.linear.flip

x == 1