SOLUTION: If a, b and c are the sides of a triangle, and a^2 + b^2 + c^2 = bc + ca + ab, then the triangle is a. equilateral b. isosceles c. right-angled d. obtuse-angled

Algebra ->  Triangles -> SOLUTION: If a, b and c are the sides of a triangle, and a^2 + b^2 + c^2 = bc + ca + ab, then the triangle is a. equilateral b. isosceles c. right-angled d. obtuse-angled      Log On


   



Question 353559: If a, b and c are the sides of a triangle, and a^2 + b^2 + c^2 = bc + ca + ab, then the triangle is
a. equilateral b. isosceles c. right-angled d. obtuse-angled

Found 2 solutions by edjones, sofiyac:
Answer by edjones(8007) About Me  (Show Source):
You can put this solution on YOUR website!
a.
Let all the side be 3
a^2 + b^2 + c^2=9+9+9
bc + ca + ab=9+9+9
.
Ed

Answer by sofiyac(983) About Me  (Show Source):
You can put this solution on YOUR website!
a) equilateral
say each side is x, so when you follow the formula you will get a=b=c=x
x%5E2%2Bx%5E2%2Bx%5E2=x%5E2%2Bx%5E2%2Bx%5E2
3x%5E2=3x%5E2 so they are equal