Question

On a town map, each unit of the coordinate plane represents 1 mile. Three branches of a bank are located at A(−3, 1), B(4, 3), and C(2, −1). A bank employee drives from Branch A to Branch B and then drives halfway to Branch C before getting stuck in traffic. What is the minimum total distance the employee may have driven before getting stuck in traffic? Round to the nearest tenth of a mile if necessary.

Answer 1

Distance formula : sqrt ((x2 - x1)^2 + (y2 - y1)^2)
(-3,1)...x1 = -3 and y1 = 1
(4,3)...x2 = 4 and y2 = 3
now we sub
d = sqrt ((4 - (-3)^2 + (3 - 1)^2)
d = sqrt ((4 + 3)^2 + (2^2))
d = sqrt (7^2 + 2^2)
d = sqrt (49 + 4)
d = sqrt 53
d = 7.28 ...so its 7.28 miles from A to B

d = sqrt ((x2 - x1)^2 + (y2 - y1)^2)
(4,3)...x1 = 4 and y1 = 3
(2,-1)...x2 = 2 and y2 = -1
now we sub
d = sqrt ((2 - 4)^2 + (-1 - 3)^2)
d = sqrt (-2^2) + (-4^2)
d = sqrt (4 + 16)
d = sqrt 20
d = 4.47....but the employee only drives halfway....so this trip was 4.47/2 = 2.235

so the minimum total distance is : 7.28 + 2.235 = 9.515  rounds to 9.5 miles