Question

7 $7^ {2x-16} \geq \frac{1}{49}$

Answer 1

$7^{2x-16} \geq \frac{1}{49}\\\\7^{2x-16} \geq 7^{-2}\\\\2x-16 \geq -2\\\\2x \geq 14\\\\x \geq 7\\\\x\in [\, 7,+\infty)$

Answer 2

$7^{2x-16} \geq \frac{1}{49} \\ \\ 7 ^{2x-16} \geq 7 ^{-2} \\ \\ 2x-16 \geq -2 \\ 2x \geq -2+16 \\ 2x \geq 14 \\ x \geq 7$

x ∈ $[7;+ \infty )$