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Question

5.) 3^(x^2)+9x = 0
6.) 8 (8^x)= 16^(3x)

Answer 1

6.) 8 ( 8^x )= 16^( 3x )

8^(1+x) = 16^(3x)

2^3(1+x) = 2^4(3x)

Bases are equal.

3(1+x) = 4(3x)

3 +3x  = 12x

Subtract  3x  in the above equation

9x = 3

Divide each side by 9.

x = 1/9

The solution is  x = 1/9