Posted by jane on Monday, October 24, 2011 at 9:14am.
recall that speed is distance travelled over time.
let x = speed of the other car.
then we set-up the equation.
when you draw the directions they're travelling, you will form a right triangle. thus recall that in a right triangle, the hypotenuse (in this the the distance between them which is 100 miles) is given by the Pythagorean theorem:
c^2 = a^2 + b^2
we equate distances:
100^2 = (40*2)^2 + (2x)^2
10000 = 80^2 + 4x^2
10000 - 6400 = 4x^2
3600 = 4x^2
x^2 = 900
x = 30 mph
hope this helps~ :)
thanks
Related Questions
math - Two cars leave the same point at noon. One car travels North and the ...
math - two cars leave the same point at noon. one car travels north and the ...
algebra 2 - two cars leave an intersection. one car travels north; the other ...
calculus - Q#1: From a point of O, two cars leave at the same time. One car ...
College Physics - suppose the two cars are headed in the same direction. A ...
math - Currently, the Toyota Corolla is the best selling car in the world. ...
math - Currently, the Toyota Corolla is the best selling car in the world. ...
Help again...Math!! - Two cars leave town going in the same direction. One ...
math - Currently, the Toyota Corolla is the best selling car in the world. ...
physics - Cars A and B are racing each other along the same straight road in the...
For Further Reading
