SOLUTION: Find 4 values for k so that (-1,2), (-10,5) and (-4,k) are the vertices of a right triangle.

Algebra ->  Triangles -> SOLUTION: Find 4 values for k so that (-1,2), (-10,5) and (-4,k) are the vertices of a right triangle.      Log On


   



Question 717966: Find 4 values for k so that (-1,2), (-10,5) and (-4,k) are the vertices of a right triangle.
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Starting with Distance Formula, First take the square of distance between each point.

One variable assigning form can give like this:
D[1] (-1,2) to (-10,5), D%5B1%5D%5E2=90
D[2] (-1,2) to (-4,k), D%5B2%5D%5E2=9%2B%282-k%29%5E2
D[3] (-10,5) to (-4,k), D%5B3%5D%5E2=36%2B%285-k%29%5E2

Three equations using pythagorean theorem can be written for those distance squared expressions:
D%5B1%5D%5E2=D%5B2%5D%5E2%2BD%5B3%5D%5E2,
and
D%5B2%5D%5E2=D%5B1%5D%5E2%2BD%5B3%5D%5E2,
and
D%5B3%5D%5E2=D%5B1%5D%5E2%2BD%5B2%5D%5E2

Take the expressions for each and fill into the pythagorean theorem equations, and solve for k. I did not finish the solution beyond what I wrote and posted so far.