Answer:
5a^4+a^2b−6b^2
Step-by-step explanation:
1. Use the FOIL method: (a+b)(c+d)=ac+ad+bc+bd.
5a^4+6a^2b−5ba^2−6b^2
2. Collect like terms.
5a^4+(6a^2b−5a^2b)−6b^2
3. Simplify.
5a^4+a^2b−6b^2
