Answer:
(a) 85 - (35 x 2) - 6
Step-by-step explanation:
The miles Mr. Richardson has left to drive will be the difference between the distance to his goal and the miles he has alread driven. The relation between distance, speed, and time can be used to find the miles he drove before lunch.
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distance = speed × time
miles before lunch = (35 mi/h) × (2 h) = (35 × 2) mi
The total miles driven before stopping for gas will be ...
miles before stopping for gas = (miles before lunch) + (6 more miles)
= 35 ×2 +6 . . . miles
Then the remaining miles are ...
remaining = trip miles - miles driven
= 85 -(35 ×2 +6)
= 85 - (35 ×2) -6 . . . . . miles left to drive