b c
- 7*k - 3*b + 3*c + 7*k + a*b - a*c
ab−ac−3b+3c−7kb+7kc b c
- 7*k + 3*c + 7*k + b*(-3 + a) - a*c
−ac+b(a−3)+3c−7kb+7kc b c
- 7*k + 7*k + b*(-3 + a) + c*(3 - a)
b(a−3)+c(3−a)−7kb+7kc b c
- 7*k - 3*b + 3*c + 7*k + a*(b - c)
a(b−c)−3b+3c−7kb+7kc b c
- 7*k - 3*b + 7*k + a*b + c*(3 - a)
ab−3b+c(3−a)−7kb+7kc