[tex]\text{Find how much Zelda paid for the visit to the ER:}\\\\\text{We know that her insurance pay's 85\% of the emergency room cost,}\\\text{ so multiply 0.85 from 4089 and subtract}\\\\4089*0.85=3,475.65\\\\4089-3,475.65=613.35\\\\\text{She pays \$613.35 of the emergency room cost}\\\\\text{We're not done yet, we also know she pays a \$100 deductible,}\\\\\text{So add 100 to 613.35}\\\\613.35+100 = 713.35\\\\\boxed{\text{She pays \$713.35}}[/tex]