Margaret traveled 80 miles to the appointment.
Step-by-step explanation:
Given,
Speed while driving for appointment = 80 mph
Speed while coming back = 70 mph
Let,
x be the time taken for the trip
y be the distance covered
Distance = Speed*Time
y = 80x Eqn 1
Time taken in return trip = x+1/7
y = 70(x+1/7)
Eqn 2
Putting value of y from Eqn 1 in Eqn 2
Dividing both sides by 10
x = 1 hour
Putting x = 1 in Eqn 1
Margaret traveled 80 miles to the appointment.
Keywords: linear equation, substitution method
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