A. 12xyz + 5xyz = (12 + 5)xyz = 17xyz
B.
- 3z³ + 4z³ = ( - 3 + 4)z³ = z³
C.
- 2x³y²y - 11 x³y² = queda igual porque sus partes literales no son iguales.
D. 15a³b³c y + 19 a³b³c = (15 + 19)a³b³c = 34a³b²c
E.
<img src="https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7B2%7D%20m%5E%7B2%7D%20n-%5Cfrac%7B1%7D%7B3%7D%20m%5E%7B2%7Dn%3D%28%5Cfrac%7B1%7D%7B2%7D-%5Cfrac%7B1%7D%7B3%7D%29%20m%5E%7B2%7D%20n%3D%5Cfrac%7B1%7D%7B6%7D%20m%5E%7B2%7D%20n%20" />
F.
<img src="https://tex.z-dn.net/?f=%20-%5Cfrac%7B4%7D%7B5%7D%20ab%20%2B%202ab%20%3D-%5Cfrac%7B4%7D%7B5%7D%20%2B2ab%3D%5Cfrac%7B6%7D%7B5%7D%20ab" />
G.
3a²m² y - <img src="https://tex.z-dn.net/?f=%20%20-%20%5Cfrac%7B5%7D%7B3%7D%20%20a%5E%7B2%7D%20%20m%5E%7B2%7D%20%3D%203-%5Cfrac%7B5%7D%7B3%7D%20%20a%5E%7B2%7D%20%20m%5E%7B2%7D%20%3D%20%5Cfrac%7B4%7D%7B3%7D%20%20a%5E%7B2%7D%20%20m%5E%7B2%7D%20" />
H.
<img src="https://tex.z-dn.net/?f=-%20%5Cfrac%7B11%7D%7B10%7D%20x%5E%7B2%7D%20z-%20%5Cfrac%7B7%7D%7B9%7D%20x%5E%7B2%7D%20z%3D%28-%20%5Cfrac%7B11%7D%7B10%7D%20-%20%5Cfrac%7B7%7D%7B9%7D%29%20x%5E%7B2%7D%20z%3D%20-%5Cfrac%7B29%7D%7B90%7D%20%20x%5E%7B2%7D%20z%20%20%20" />.