Answer:
Step-by-step explanation:
[tex]a^{m}*a^{n}=a^{m+n}\\\\9^{10}*9^{x}=9^{10+x}[/tex]
In exponent multiplication, if the bases are same then add the exponents.
[tex] \small \sf \leadsto 9 {}^{10 +x} [/tex]
Step-by-step explanation:
Using exponent's product rule
[tex] \small \sf \: x {}^{n} \times x {}^{m} = x {}^{n + m} [/tex]
[tex] \small \sf \leadsto \: 9 {}^{10} \times 9 {}^{x} [/tex]
[tex] \small \sf \leadsto 9 {}^{10 + x} [/tex]