SOLUTION: two cars leave an intersection, one car travels north the other east. When the car traveling north had gone 12 miles the distance between the cars was 8 miles more than the distanc

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: two cars leave an intersection, one car travels north the other east. When the car traveling north had gone 12 miles the distance between the cars was 8 miles more than the distanc      Log On


   



Question 283303: two cars leave an intersection, one car travels north the other east. When the car traveling north had gone 12 miles the distance between the cars was 8 miles more than the distance traveled by the car heading east. how far had the eastbound car traveled?
Found 2 solutions by richwmiller, oberobic:
Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
12^2+b^2=(b+8)^2
144+b^2=b^2+16x+64
144=16x+64
80=16x
5=x
a classic 5,12,13 right triangle triplet

Answer by oberobic(2304) About Me  (Show Source):
You can put this solution on YOUR website!
This is an interesting application of the Pythagorean Theorem.
The car traveling north can be viewed as going up the y-axis 12 units.
The car going east can be be viewed as going to the right along the x-axis.
It has traveled 'd' miles.
The diagonal from that connects the two cars is the hypotenuse of a right triangle.
It's length is d+8, which is given.
.
12^2 + d^2 = (d+8)^2
144 + d^2 = d^2 +16d + 64
subtract d^2 from both sides
144 = 16d + 64
subtract 64 from both sides
80 = 16d
divide both sides by 16
5 = d
d = 5
.
Check to ensure diagonal 'c' is 5+8 =13.
c^2 = 12^2 + 5^2
c^2 = 144 + 25
c^2 = 169
So, c = 13
Correct.
.
Answer:
The eastbound car has travelled 5 miles.
.
Done.