anybody in connexus that can help me?

Question

welshfella · Answer

what is your question?

anonymous · Answer

i need help on lesson 8.
"what is the perimeter of triangle PQR with the vertices P(-2,9) Q(7,-3) R(-2,-3) in the coordinate plane?"

welshfella · Answer

you need to find the distances between the points of the triangle

the distance formula for 2 points in the coordinate plane is

d = sqrt([( y2-y1)^2 + (x2 - x1)^2 ]

where the 2 points are (x1,y1) and (x2,y2)

welshfella · Answer

so the distance between the points P and Q is

sqrt  [ (9 - (-3))^2 +  ( -2 - 7)^2] 

=   sqrt ( 144 +  81)
=   sqrt 225  = 15

welshfella · Answer

now you need to find the lengths of the other 2 sides QR and RP by the same method and then the perimeter = sum of these 3 lengths