Step-by-step explanation:
[tex]-18+8x\geq50\qquad\text{add 18 to both sides}\\\\-18+18+8x\geq50+18\\\\8x\geq68\qquad\text{divide both sides by 8}\\\\\dfrac{8x}{8}\geq\dfrac{68}{8}\\\\x\geq8.5\to x\in[8.5,\ \infty)[/tex]
