Which expressions are equivalent to the one below? Check all that apply.21^x/7x A. 3^x-7B. 3C. 3^xD. (21-7)^xE. 7^x * 3^x/ 7^xF. (21/7)^x

The expression (21ˣ/7ˣ) is equivalent to the expression 3ˣ. Then the correct option is C.What is an equivalent expression?The equivalent is the expression that is in different forms but is equal to the same value.The expression is given below.[tex]\rightarrow \rm \dfrac{21^x}{7^x}[/tex]The expression can be written as [tex]\rightarrow \rm \left ( \rm \dfrac{21^x}{7^x} \right )\\\\\\\rightarrow \left ( \rm \dfrac{21}{7} \right )^x\\\\\\\rightarrow 3^x[/tex]More about the equivalent expression link is given below.