Question

A Toyota Prius and a Dodge Circuit leave an intersection at the same time. The Prius heads east at an average speed of 50 miles per hour, while the Circuit heads south at an average speed of 45 miles and hour. After 30 minutes, the two cars are about _____ miles apart. After 2 hours, the two cars are about ______ miles apart. Write an express for the distance, d (in miles) after t hours.

Answer 1

Answer:

33.634 ; 134.536 ; d = √[(50t)² + (45t)²]

Step-by-step explanation:

Given the following :

Toyota Prius = East at 50mph

Dodge Circuit = South at 45mph

Distance apart after 30 minutes :

Distance = speed * time

Distance moved by Prius = ( 50mph × 0.5hr) = 25 miles

Distance moved by Circuit = ( 45mph × 0.5hr) = 22.5 miles

Hence Displacement after 30 minutes :

d = √(25² + 22.5²)

d = √625 + 506.25

d = √1131.25

d = 33.634 miles

Distance apart after 2 hours :

Distance = speed * time

Distance moved by Prius = ( 50mph × 2hr) = 100 miles

Distance moved by Circuit = ( 45mph × 2hr) = 90 miles

Hence Displacement after 2 hours :

d = √(100² + 90²)

d = √10000 + 8100

d = √18100

d = 134.536 miles

Distance d in miles after t hours :

d = √[(50t)² + (45t)²]