Question

Determine X em cada caso :
a)
b)
c)

Answer 1

Resolução da questão, veja:

Letra “A”:

$\mathsf{5^{x+2} = 625}}\\\\\\\\\ \mathsf{\diagup\!\!\!\!5^{x+2} = \diagup\!\!\!\!\!\!5^{4}}\\\\\\\\\ \mathsf{x + 2 = 4}}\\\\\\\\\ \mathsf{x=4-2}}\\\\\\\\\\ \large\boxed{\boxed{\boxed{\boxed{\boxed{\boxed{\mathsf{x=2.}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}$

Letra “B”:

$\mathsf{3^{x+2} = \dfrac{1}{81}}\\\\\\\\\ \mathsf{3^{x+2} = \dfrac{1}{3^{4}}}}}\\\\\\\\\\ \mathsf{\diagup\!\!\!\!\!3^{x+2} = \diagup\!\!\!\!\!\!3^{-4}}}}}}}}}\\\\\\\\\\ \mathsf{x+2=-4}}\\\\\\\\\ \mathsf{x= -4-2}}\\\\\\\\\ \large\boxed{\boxed{\boxed{\boxed{\boxed{\boxed{\mathsf{x = -6.}}}}}}}}}}}}}}}}}}}}}}}}}}$

Letra “C”:

$\mathsf{2^{3x+2} = 512}}\\\\\\\\\ \mathsf{\diagup\!\!\!\!\!\!\!2^{3x+2} = \diagup\!\!\!\!\!\!\!2^{9}}\\\\\\\\\\\ \mathsf{3x+2 = 9}}\\\\\\\\ \mathsf{3x = 9-2}}\\\\\\\\\ \mathsf{3x=7}}\\\\\\\\\\ \large\boxed{\boxed{\boxed{\boxed{\boxed{\boxed{\mathsf{x= \dfrac{7}{3}}}}}}}}}}}}}}}}}}}}}}}}}}$

Espero que te ajude '-'