Geometry math question

Question

Two sides of a triangle have lengths 4 and 7. Which of the following can NOT be the length of the third side.

A)5

B)4

C)7

D)11

Answer 1

D) 11

 

Since 4 + 7 = 11, there is not enough length for the two sides 4 & 7 to 'form a peak' or an angle away from the side of 11 length.

 

Theorem: The sum of the lengths of any two sides of a triangle must be greater than length of  the third.

 

A²