Two sides of a triangle have lengths 10 and 15. What must be true about the length of the third side? Select one: a. less than 25 b. less than 10 c. less than 15 d. less than 5

Answer 1

Given sides A,B, and C,

A+B>C

B+C>A

A+C>B]

You can use either equation to determine the length of the third side.

10+15>C

Solve for length of 3rd side (C)

25>C OR C<25, therefore, the length of the third side must be less than 25

Answer 2

Draw a Picture

Start by drawing the 2 lines with a very small angle between them. The 3rd side must be greater than 0--otherwise there would be no triangle.

Similarly, draw the two lines end-to-end,with the angle between them almost 180 degrees. From this, we can see that the 3rd side would have to be less than 25 (fixed previous error)

Continue this thought process