Question

A triangle has two sides of length 3.2 cm and 8.5 cm.

Which value could be the length of the third side of the triangle?

Answer Choices-
3.7 cm
3.7 cm

5.3 cm
5.3 cm

6.7 cm
6.7 cm

15.8 cm

Answer 1

Answer: 6.7 cm

Explanation:

If I'm correct, the third side of any triangle is less than the sum of the other two sides and greater than the difference of the smaller from the larger side of the two known values.

c < b+a

c > b-a (b > a)

Knowing this, we can use some quick arithmetic:

(8.5-3.2) < c < (3.2+8.5)

5.3 < c < 11.7

Looking through the answer choices, the only correct answer is 6.7 cm. Hope this helps!