Question

You are asked to draw a triangle with side lengths of 8 inches and 10 inches. What is the longest whole number length that your third side can be?
20
18
21
16

Answer 1

Answer:

18 inches

Step-by-step explanation:

The largest angle on a triangle can be 178°. So you can find the largest side using the cosine rule. c² = a²+b²-2abCosC

Answer 2

The largest whole number length of the third side will be 16 inches.

Step-by-step explanation:

Two sides of the triangle to be drawn are 8 inches and 10 inches.

We have to determine the largest length in whole number of the third side.

Let, the third side length is a inches,

So, the length of a is governed by the relation

(10 - 8) < a < (10 + 8)

⇒ 2 < a < 18

Therefore, the largest value of a in the whole number is 17, but 17 is not in options.

Hence, the largest whole number length of the third side will be 16 inches. (Answer)