Patricia's teacher asked her to find the perimeter of the school's rectangular parking lot. After school, patricia walks along the short side of the lot and finds it is 50 yards long. She then walks diagonally from one corner of the rectangle to the other and throught the exit to go home. She finds that the distance of the diagonal is 130 yards. Patricia decides that this is enough information to determine the perimeter of the track. Based on her information, what is the perimeter of the parking lot?

Question

Patricia's teacher asked her to find the perimeter of the school's rectangular parking lot.  After school, patricia walks along the short side of the lot and finds it is 50 yards long.  She then walks diagonally from one corner of the rectangle to the other and throught the exit to go home.  She finds that the distance of the diagonal is 130 yards.  Patricia decides that this is enough information to determine the perimeter of the track.  Based on her information, what is the perimeter of the parking lot?

so I did 50^2 + b^2 = 130^2

2500+b^2=16,900
b^2=14,400
b=120

so the choices are:

a. 100 yards
b. 110 yards
c. 120 yards
d. 180 yards

But I get for the perimeter
50+50+120+120=340
what am I doing wrong?

Reiny · Answer

If the question is as you typed it, there is nothing that you did wrong.
I recognized your dimensions as multiples of 10 of the basic 5,12, 13 right-angled triangle.

It wouldn't be the first time that a textbook has wrong answers.