Answer: <em>x=4</em>
Step-by-step explanation:
<em>1+3x=x+9</em>
<em> -x -x</em>
<em>1+2x=9</em>
<em>-1 -1</em>
<em>2x=8</em>
<em>Divide by 2 on each side</em>
<em>Final result</em>
<em>x=4</em>
One of the product rules for exponents was used.

Or, you can consider that the definition of an exponent and the associative and commutative properties of multiplication were used.
Answer:
infinite
Step-by-step explanation:
name two, and then find a third in between them.
you can repeat that as often as you want.