Answer:
Explanation:
1) Makes a triangle. 6+8>10 In fact this one makes a right triangle. Try it using a = 6 b = 8 c = 10
2) 6 + 12 should exceed the third side. If these two just equal the third side (as these two do) then no triangle is formed.
3) Same with this one 7 + 1 = 8. No triangle is formed. Just a straight line
4) This one is fine. It makes an isosceles triangle with 2 sides = to 7. Any 2 are bigger than the third.