If this is an option, it should be Similar Triangles.
The equation that models the sequence is: 6+6 each time.
Answer:
12.4 gallons
Step-by-step explanation:
65 mph x 4 hours means the car went 260 miles. Divide by 21 to get the number of gallons. 12.4 gallons.
I'm pretty sure that it is C. 12
