Exercise algebra.equations.linear.balance

Description
Solve a linear equation using only balance rules.

Derivation

12+5*(x-1) == 4*x-(x-2)
algebra.equations.linear.balance.distribute
12+5*x-5 == 4*x-x+2
algebra.equations.linear.balance.collect
7+5*x == 3*x+2
algebra.equations.linear.balance.var-left-minus, term=3*x
7+2*x == 2
algebra.equations.linear.balance.con-right-minus, term=7
2*x == -5
algebra.equations.linear.balance.scale-to-one, factor=2
x == -5/2