please help me and we should use laws of exponents

Answer:
3.b
[tex](\frac{8}{3})^{2x+1} *(\frac{8}{3})^{5} =(\frac{8}{3}) ^{x+2}\\\\(\frac{8}{3})^{2x+1 +5} =(\frac{8}{3}) ^{x+2}\\\\\\2x +6 = x+2\\x = -4[/tex]
i hope question 3.a. is 5^x ÷ 5^-3 = 5^5
3.a.
[tex]\frac{5^x}{5^{-3}} = 5^5\\\\5^ {x+3} = 5^5\\\\x+3 = 5\\x =2[/tex]