Answer: [tex]y^9[/tex]
Step-by-step explanation:
The product law of exponent says that for any arbitrary number a, we have:
[tex]a^m\times a^n=a^{m+n}[/tex], where powers m and n are any number.
The given expression: [tex]y^4\cdot y^5[/tex]
Using product law of exponents , we get
[tex]y^4\cdot y^5\\\\=y^{4+5}\\\\=y^9[/tex]
Hence, the simplified expression of the given expression is [tex]y^9[/tex].
