SOLUTION: Find X if the distance between points A and B is 13 and B is located in the second quadrant. A=(5,-1) B=(x,4)

Algebra ->  Graphs -> SOLUTION: Find X if the distance between points A and B is 13 and B is located in the second quadrant. A=(5,-1) B=(x,4)      Log On


   

Question 1139671: Find X if the distance between points A and B is 13 and B is located in the second quadrant.
A=(5,-1)
B=(x,4)
Answer by ikleyn(52832) About Me  (Show Source):
You can put this solution on YOUR website!
.
%285-x%29%5E2 + %28%28-1%29-4%29%5E2 = 13%5E2


25-10x%2Bx%5E2 + 5%5E2 = 169


25+-+10x+%2B+x%5E2 + 25 = 169


x%5E2+-+10x+-+119 = 0.


(x-17)*(x+7) = 0


There are two roots x= 17  and  x= -7,  and only negative root x= -7  provides the point B in QII.


ANSWER.  x = -7.