algebra 2
posted by amanda .
two cars leave an intersection. one car travels north; the other east. when the car traveling north had gone 15 miles, the distance between the cars was 5 mile more than the distance traveled by the car heading east.how far had the east bound car traveled?

A rt. triangle is formed:
X miles = hor side.
15 miles = ver. side.
x+5 = hyp.
x^2 + 15^2 = (x+5)^2.
x^2 + 225 = x^2 + 10x + 25.
x^2  x^2 + 10x = 225  25 = 200.
10x = 200.
X = 200 / 10 = 20 miles.