Question

Jamal has 2 straight sticks with lengths of 20cm and 18cm. Jamal searches for a third stick so that he can form a triangle. Which lengths of a stick will allow jamal to make a triangle.

Answer 1

A. 36 cm

Explanation:

Let x represent the 3rd side length of triangle.

Please consider the complete question.

Jamal has 2 straight sticks with lengths of 20 cm and 18 cm. Jamal searches for a third stick so that he can form a triangle. Jamal searches for a third stick so that he can form a triangle. Which lengths of a stick will allow jamal to make a triangle.

A. 36 cm B. 38 cm

C. 40 cm D. 42 cm

We will use triangle inequality theorem to solve our given problem.

Triangle inequality theorem states that sum of measures two sides of triangle should me always greater than measure of 3rd side.

We can set 2 inequalities as:

`x+18>20...(1)`

`x+18-18>20-18...(1)`

`x>2...(1)`

`18+20>x...(2)`

`38>x...(2)`

`x<38...(2)`

This means that third side of triangle should be greater than 2 and less than 38.

Since 36 is greater than 2 and less than 38, therefore, option A is the correct choice.