Two sides of a triangle have lengths 11 and 18. What must be true about the length of the third side?
A less than 38
B less than 18
C less than 29
D less than 11

Question

Two sides of a triangle have lengths 11 and 18. What must be true about the length of the third side?
A less than 38
B less than 18
C less than 29
D less than 11

sshayer · Answer

what do you think?

mathstudent55 · Answer

Here you have two segments that have a common endpoint.
You can think of the two segments as sides of a triangle with the third side missing.
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mathstudent55 · Answer

The two sides of the triangle are AB with length x and BC with length y.
How long can the third side of the triangle be?
If you swing side BC down to the left until just before it makes a line with side AB, that is the longest length you will get for side AC.
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