# SOLUTION: Show that the points R (-1 , 2), K (5 , 2) and O (2 , 5) are the vertices of an isosceles triangle. Find the area of triangle RKO. :) =)

Algebra ->  Algebra  -> Coordinate-system -> SOLUTION: Show that the points R (-1 , 2), K (5 , 2) and O (2 , 5) are the vertices of an isosceles triangle. Find the area of triangle RKO. :) =)       Log On

 Ad: Algebrator™ solves your algebra problems and provides step-by-step explanations! Ad: Algebra Solved!™: algebra software solves algebra homework problems with step-by-step help!

 Algebra: Coordinate systems, graph plotting, etc Solvers Lessons Answers archive Quiz In Depth

 Click here to see ALL problems on Coordinate-system Question 403267: Show that the points R (-1 , 2), K (5 , 2) and O (2 , 5) are the vertices of an isosceles triangle. Find the area of triangle RKO. :) =) Answer by Alan3354(30927)   (Show Source): You can put this solution on YOUR website!Show that the points R (-1,2), K (5,2) and O (2,5) are the vertices of an isosceles triangle. ------------------- Find the lengths of RO and KO For RO: For KO: They're the same length --> isoceles. The length of KR = 6 --> not equilateral. --------------------- --------------------- Find the area of triangle RKO. ---------------- Write the points in columns, repeating the 1st point R K O R -1 5 2 -1 +2 2 5 +2 ---------- Add the diagonal products from upper left: (-1*2) + 5*5 + 2*2 = 27 Add the diagonal products from lower left: 2*5 + 2*2 + 5*(-1) = 9 ------------------ The area = 1/2 the difference Area = (1/2)*(27-9) = 9 sq units