Answer:
<h3>B. 6x.</h3>
Step-by-step explanation:
Given two sides of a triangle 2x – 4 and 7x – 2 units.
<em>Difference of two sides of a triangle is less than third side.</em>
Let us find the difference of 7x – 2 and 2x – 4, we get
7x-2 - (2x-4) = 7x -2 -2x +4
= 5x + 2.
Third side should be less then 5x+2, so 5x+2 can't be third side.
<em>Sum of two sides is greater than third side.</em>
Adding given sides of triangle, we get
7x-2 +2x-4 = 9x - 6.
Third side should be greater than 9x-6. So, 9x-6 can't be third side.
Now, if we add 3x and 2x-4, we get
3x+2x-4 = 5x-4, which is less than 9x - 6.
So, 3x can't be third side.
Therefore, correct option is :
<h3>B. 6x</h3>