The distance between two points A (2,u) and B (-3,4) is 5. What is the value of u?

PLEASE HELP ME!!!!!

Also could you please include which formula you use to work out u, and full working out?
Thankyou! :) :) :)

1 Answer
May 1, 2018

#u=4#

Explanation:

Remember the distance formula:

#d=sqrt((x_2-x_1)^2+(y_2-y_1)^2)#

We let #A# represent #(x_1,y_1)# and #B# represent #(x_2,y_2)#

Therefore:

#x_1=2# #x_2=-3# #y_1=u# and #y_2=4#

The distance is 5.

We now have:

#5=sqrt((-3-2)^2+(4-u)^2)#

#=>5^2=(-5)^2+(4-u)^2#

#=>25=25+(4-u)^2#

#=>0=(4-u)^2#

#=>+-sqrt0=4-u#

#=>0-4=-u#

#=>4=u#