Set 1: Systems of Equations

Choice C is correct. Choice C is the correct answer. When riding toward each other, they close the gap at the sum of their speeds. Let $t$ = time in hours. Combined speed: $12+ 18 = 30$ mph Equation: $$$30t = 90t = 3$$ Solution: 3 hours Verification: In 3 hours: - Cyclist 1: 12(3) = 36$miles - Cyclist 2:$18(3) = 54$ miles - Total: $36+ 54 = 90$ miles ✓ Strategic Tip: Toward each other → add speeds. Other choices based on calculation.