Respuesta :

leguchi
12g + 9(g-20)

Distribute with distributive property
12g + 9g - 9*20

Simplify
21g -180

I hope this is what you're looking for?

And it can also be expressed as 3(7g - 60)
12g+9(g-20)
=12g+9g-180
=21g-180. Hope it help!