Atriangle has side lengths of 17 cm and 5 cm. which could be the value of the third side, 27 cm or 20 cm?

For a triangle to be possible, the sum of two of its side lengths cannot be greater than or equal to the third side length. The sum of the given side lengths is 17+5=22 cm. So the third side length must be shorter than 22cm. 27cm is longer than 22cm, while 20cm is shorter. So the third side could be 20cm.